Keeler KAT R User manual

Keeler Applanation
Tonometer (KAT)
R type and T type
INSTRUCTIONS FOR USE
EN HY RU

EN
HY
RU
KAT R տիպի և T տիպի տոնոմետր
Օգտագործման հրահանգներ.....................................................22
KAT R Type and T Type Tonometer
Instructions For Use ..................................................1
Тонометр KAT типа R и типа Т
Инструкция по эксплуатации............................................................43

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KAT R Type and T Type Tonometer by KEELER
CONTENTS
1. INDICATIONS FOR USE ......................................................................................... 3
1.1 BRIEF DESCRIPTION OF THE INSTRUMENT ................................................................................3
1.2 INTENDED USE / PURPOSE OF INSTRUMENT............................................................................3
1.3 HOW THE INTRAOCULAR PRESSURE (IOP) IS MEASURED................................................3
1.4 ADVANTAGES OF USING A GOLDMANN TYPE TONOMETER .........................................3
2. SAFETY........................................................................................................................ 4
2.1 WARNINGS AND CAUTIONS............................................................................................................ 4
2.2 CONTRAINDICATION........................................................................................................................... 5
3. CLEANING AND DISINFECTION INSTRUCTIONS ............................................ 6
3.1 CLEANING TONOMETER BODY.......................................................................................................6
3.2 DISINFECTING THE TONOMETER PRISMS .................................................................................6
4. TONOMETER PRISM FIELD CHECK ..................................................................... 7
5. NAME OF COMPONENTS ...................................................................................... 8
6. MEASUREMENT PROCEDURE............................................................................... 8
6.1 INSTALLATION ON TO THE SLIT LAMP......................................................................................... 8
6.2 PREPARING THE PATIENT................................................................................................................... 9
6.3 PREPARING THE SLIT LAMP INSTRUMENT FOR EXAMINATIONS AT 10X
MAGNIFICATION...................................................................................................................................10
6.4 USING THE INSTRUMENT / TAKING A MEASUREMENT.......................................................11
6.5 TAKING THE MEASUREMENT............................................................................................................11
7. PROBLEM SOLVING................................................................................................12
7.1 THE FLUORESCEIN RING IS TOO WIDE OR TOO NARROW .............................................12
7.2 THE MEASUREMENT PRISM DOES NOT TOUCH THE CORNEA OR TOO MUCH
FORCE HAS BEEN APPLIED...............................................................................................................13
7.3 THE TWO SEMICIRCLES ARE NOT CENTRAL IN THE FIELD OF VISION.......................13
7.4 THE INSIDE MARGINS OF THE FLUORESCEIN RINGS ARE NOT ALIGNED AND
TOUCHING ...............................................................................................................................................14
8. GENERAL INFORMATION AND SUGGESTIONS CONCERNING
MEASUREMENT .......................................................................................................15
9. ASTIGMATISM .........................................................................................................16
10. ROUTINE INSTRUMENT MAINTENANCE........................................................... 17
10.1 CHECK PROCEDURE WITH THE MEASUREMENT DRUM SET TO 0..............................17
10.2 CHECK PROCEDURE WITH MEASUREMENT DRUM SET TO 2........................................17
11. SERVICING AND CALIBRATION..........................................................................18
12. WARRANTY ..............................................................................................................19
13. TECHNICAL SPECIFICATIONS ............................................................................19
14. ACCESSORIES AND SPARES ..............................................................................20
15. PACKAGING AND DISPOSAL INFORMATION.................................................21

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KAT R Type and T Type Tonometer by KEELER
Consult instructions for use General warning sign
Date of manufacture Warning: Non-ionizing radiation
Manufacturer’s name and
address Keep dry
Country of manufacture Fragile
Waste Electrical and Electronic
Equipment (WEEE) recycling
Do not use if package is
damaged
This way up Class II equipment
Temperature limit Medical device
Catalogue number Serial number
0120
United Kingdom Conformity
Assessed, with the Notified
Body number for SGS UK 1639
Conformité Européene, with the
Notified Body number for SGS
Belgium NV
REPEC
Authorised representative in the
European Community
REPCH
Authorised representative in
Switzerland
Atmospheric pressure limitation Humidity limitation
Translation
The Keeler KAT Tonometer is designed and built in conformity with Directive 93/42/EEC, Regulation (EU) 2017/745
and ISO 13485 Medical Devices Quality Management Systems.
Classification: CE / UKCA: Class Im
FDA: Class II
The information contained within this manual must not be reproduced in whole or part without the manufacturer’s
prior written approval.As part of our policy for continued product development we the manufacturer reserve the right
to make changes to specifications and other information contained in this document without prior notice.
This IFU is also available on the Keeler UK and Keeler USA websites.
Copyright © Keeler Limited 2023. Published in the UK 2023.

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KAT R Type and T Type Tonometer by KEELER
1. INDICATIONS FOR USE
These devices are intended to be used only by suitably trained and authorised healthcare
professionals.
The KAT should be used only by trained personnel. USA Federal law
restricts this device to sale by or order of a physician.
1.1 BRIEF DESCRIPTION OF THE INSTRUMENT
The Keeler Applanation Tonometer operates according to the “Goldmann method”, by
measuring intraocular pressure from the force required to flatten (applanate) a constant
area (3.06 mm) of the cornea. A special disinfected (or single use) prism is mounted on the
Tonometer head and then placed against the cornea.
The examiner, using a slit lamp biomicroscope at 10x magnification, with a blue filter views
two fluorescing green semicircles. The force applied to the Tonometer head is then adjusted
using the dial until the inner edges of these green semicircles meet.
Because physical contact with the cornea takes place, it is necessary to apply to the patient’s
cornea a suitable topical anaesthetic.
1.2 INTENDED USE / PURPOSE OF INSTRUMENT
The Keeler Applanation Tonometer is indicated for measuring intraocular pressure to aid in the
screening and diagnosis of glaucoma.
The Keeler Applanation Tonometer (KAT) is an accessory item for most ‘Tower Illumination’ type
of Slit Lamps and thanks to its versatility, the KAT Tonometer can be mounted on and used
with slit lamps produced by many manufacturers.
1.3 HOW THE INTRAOCULAR PRESSURE (IOP) IS MEASURED
The cornea is flattened by an acrylic measuring prism on a ring support at the end of the
Tonometer sensor arm assembly. It is flat with smooth or rounded margins to avoid any
damage to the cornea.
The measuring prism is brought into contact with the patient’s eye by moving the slit lamp
forward.The measurement drum is then turned to increase the pressure on the eye, until a
continuous, uniform applanated surface 3.06 mm in diameter (7,354 mm² area) is obtained.
The doubling prism divides the image and presents the two opposing semicircular halves at
3.06 mm (see Section 6.5 on page 11 Measurement procedure for further details).
1.4 ADVANTAGES OF USING A GOLDMANN TYPE TONOMETER
• Intraocular pressure can be measured during a routine examination with the Slit Lamp.
• The standard deviation among single measurements is approximately ≤ 0,5 mmHg.
• The value is expressed in mmHg and is read directly on the instrument.
• Scleral rigidity need not be taken into consideration because the small volume moved
(0,56 mm3) increases intraocular pressure by only about 2.5%.

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KAT R Type and T Type Tonometer by KEELER
• There are no difficulties as regard standardisation and calibration.
2. SAFETY
2.1 WARNINGS AND CAUTIONS
Please note that the proper and safe functioning of our instruments is only guaranteed if both
the instruments and their accessories are exclusively from Keeler Ltd.
Observe the following precautions in order to ensure safe operation of the instruments.
WARNINGS
• Never use the instrument if visibly damaged and periodically inspect it for signs of damage
or misuse.
• Check your Keeler product for signs of transport / storage damage prior to use.
• US Federal Law restricts this device to sale by or on the order of a physician or practitioner.
• The owner of the instrument is responsible for training personnel in its correct use.
• Accuracy of applanation IOP measurements is known to be affected by variations and
changes in corneal rigidity due to differences in corneal thickness, intrinsic structural
factors or corneal refractive surgery. It is recommended that these factors are considered
during IOP measurement.
• The contact surface of the prism should be checked before each use for damage and
discarded if damage is found.
• We recommend that the prism is not used when it becomes more than two years of age
as, after this time it is possible that body or sterilising fluids may seep inside leading to
possible sterility and cross contamination issues.
• Keeler Applanation Tonometers should be serviced and calibrated annually.Any servicing
or repairs / modifications should only be carried out by Keeler Ltd. or by suitably trained
and authorised distributors. The manufacturer declines any and all responsibility for loss
and / or damages resulting from unauthorised repairs; furthermore, any such actions will
invalidate the warranty.
Position of the
measurement drum
Force
mN
Pressure
kPa mmHg
19.81 1.33 10
219.62 2.66 20
329.43 39.9 30
4 39.24 53.2 40
5 49.05 66.5 50
6 58.86 79.8 60
7 68.67 93.1 70
8 78.48 10.64 80
Relationship between the pressure of
the measurement drum and the force
and pressure on the applanated surface.
The intra-ocular pressure, expressed in
mmHg, is calculated by multiplying the
drum measurement by ten (for conver-
sion from one unit to another).

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KAT R Type and T Type Tonometer by KEELER
• Only decontaminate / clean in accordance with a method given in Cleaning (Section 3) of
this instruction manual.
• Use only cloths dampened with water to clean the Applanation Tonometer body. Do not
use corrosive products or alcohol.
• Never use the instrument if the ambient temperature, atmospheric pressure, and / or
relative humidity are outside the limits specified in this manual.
• Should the instrument suffer shocks (for example, should it accidentally fall), follow the
check procedure outlined in the ‘Servicing and Calibrations’ (Section 1); if necessary, return
the instrument to the manufacturer for repair.
• Use only the listed accessories in conjunction with the instrument; use said accessories
only in accordance with the procedures set forth in the instruction manuals.
• Always carefully observe the safety rules and other precautions published herein.
• Do not use in the presence of flammable gases / liquids, or in an oxygen rich environment.
• This device is intended to be used only by suitably trained and authorised healthcare
professionals.
• This product should not be immersed in fluid.
CAUTION
• Use only genuine Keeler approved parts and accessories or device safety and performance
may be compromised.
• Keep out of the reach of children.
• To prevent condensation from forming, allow instrument to come to room temperature
before use.
• For indoor use only (protect from moisture).
• There are no user serviceable parts inside. Contact authorised service representative for
further information.
• Follow guidance on cleaning / routine maintenance to prevent personal injury / damage to
equipment.
• Failure to carry out recommended routine maintenance as per the instructions in this IFU
may reduce the operational lifetime of the product.
• At product end of life dispose of in accordance with local environmental guidelines (WEEE).
2.2 CONTRAINDICATION
There is no restriction to patient population this device can be used with and there are no
known contraindications associated with the device.
• Do not use contact tonometry on those with ruptured globe, corneal lesions, ulcer or
epithelial defects and patients that are not suitable for anesthesia administration.
• Take extra care with patients with ocular infection to prevent transmission.

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KAT R Type and T Type Tonometer by KEELER
3. CLEANING AND DISINFECTION INSTRUCTIONS
3.1 CLEANING TONOMETER BODY
Only manual non-immersion cleaning as described should be used for this instrument. Do not
use corrosive products or alcohol. Do not autoclave or immerse in cleaning fluids.
1. Wipe the external surface with a clean absorbent, non-shedding cloth dampened with
de-ionised water / detergent solution (2% detergent by volume) or water / isopropyl
alcohol solution (70% IPA by volume). Avoid optical surfaces.
2. Ensure that excess solution does not enter the instrument. Use caution to ensure cloth is
not saturated with solution.
3. Surfaces must be carefully hand-dried using a clean non-shedding cloth.
4. Safely dispose of used cleaning materials.
3.2 DISINFECTING THE TONOMETER PRISMS
Always disinfect the Tonometer prisms before use. Hand hygiene must be
considered to prevent any contamination.
1. Carefully remove the Tonometer prism
from the prism holder.
2. Wash the Tonometer prism under cold
running water for approximately 1
minute, to ensure the Tonometer prism
is physically clean before exposed to
the disinfection process.
1 min
3. Immerse the Tonometer prism in the
disinfectant fluid. Types of disinfectant
fluid vary.
4. Rinse the disinfectant from the prism
in running water for between 10 and
30 minutes.

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KAT R Type and T Type Tonometer by KEELER
10 mins 10-30 mins
Please follow disinfectant solution guidelines
for instructions, concentration and time of
immersion. (For example: Pantasept – 3%
aqueous solution for 10 minutes, Hydrogen
Peroxide 3% aqueous solution for 10 minutes,
Sodium Hypochlorite, 10% aqueous solution for
10 minutes etc.).
5. Dry the disinfected Tonometer prism
with a clean soft non-shedding cloth.
6. Store the Tonometer prism in a
suitable container ready for use.
Safely dispose of the disinfectant fluids used.
Do not disinfect using the following: Alcohol, Acetone, UV radiation,
Sterilisation, Immersion in fluid for more than one hour, Temperatures
greater than 60°C.
4. TONOMETER PRISM FIELD CHECK
Check the Tonometer prism under the Slit lamp and ensure there are no
cracks / chips. the chemical used in the diagnosis process (for example:
Fluorescein) will get into the cracks and will show up if observed under
the slit lamp. Do not use it if there is any sign of cracks / chips.

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KAT R Type and T Type Tonometer by KEELER
5. NAME OF COMPONENTS
1. Control weight housing
2. Rotating measurement knob
3. Doubling prism
4. Measurement arm
5. Manufacturers data
6. T type mounting assembly
7. R type mounting assembly
8. Calibration arm assembly
6. MEASUREMENT PROCEDURE
6.1 INSTALLATION ON TO THE SLIT LAMP
Before installing the Tonometer on a Slit Lamp ensure that they are mutually suitable and that
the tonometer is level.
Keeler Applanation Tonometer (T type)
1. Position the guide plate in the Tonometer/test bar support hole on the slit lamp.
2. Lift Tonometer out of the packaging and assemble it by inserting the pin on its base
into one of the two possible openings (for right or left eye) on the horizontal guide
plate above the slit lamp axis. These positions are related to the microscope optics and
observation can be made either through the right or the left eye-piece.
3. The Tonometer will slip easily onto the support plate; stability is assured by the locking
pins.
T type KAT (take-away)
Part number: 2414-P-2030
6
5
5
1
7
3
2
8
4
4
3
1
2
R type KAT (fixed)
Part number: 2414-P-2040

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KAT R Type and T Type Tonometer by KEELER
4. To obtain an image as clear and as
free of reflexes as possible, the angle
between the illumination and the
microscope should be about 60° and
the slit diaphragm should be fully
opened.
5. When not in use the Tonometer should
be removed from the Slit Lamp and
placed securely back in the packaging
or a suitable location.
Applanation Tonometer ‘Keeler Fixed’
(R type)
This instrument is for those who wish the
Tonometer to remain permanently on the
slit lamp.
1. Mount the plate for the Tonometer
onto the microscope body using the
securing screw.
2. Then mount the Tonometer mount onto
the mounting post.
3. Swing the Tonometer forward in front
of the microscope for examination. A
notch position ensures exact centring
of the prism with the left objective.
4. To obtain an image as clear and as
free of reflexes as possible, the angle
between the illumination and the
microscope should be about 60° and
the slit diaphragm should be fully
opened.
5. When not in use the instrument is
swung around and secured in a notch
position to the right of the microscope.
6.2 PREPARING THE PATIENT
• Use an appropriate topical anaesthetic to
numb the cornea.
• Place a strip of fluorescein-soaked paper near the outer canthus in the lower conjunctival
sac. After a few seconds, the lacrimal fluid will be coloured and the paper may be removed.
When using drops, we recommend a 0.5% solution of fluorescein sodium. If using a 1% or
2% solution, use a glass rod to introduce a small quantity of liquid into the conjunctival sac.
Mounting
Plate
R type
Guide
Plate
T type

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KAT R Type and T Type Tonometer by KEELER
• Seat the patient at the Slit Lamp and place his / her chin on the chinrest and ensure the
forehead touches the forehead rest.
• Adjust the chinrest height so that the patient’s eye is at the correct height (most Slit lamps
have a marker on the chinrest pole for correct height adjustment).
Do not disinfect using the following: Alcohol, Acetone, UV radiation,
Sterilisation, Immersion in fluid for more than one hour, Temperatures
greater than 60°C.
Check prisms for damage prior to use.
6.3 PREPARING THE SLIT LAMP INSTRUMENT FOR EXAMINATIONS AT 10X
MAGNIFICATION
• Before beginning measurement, check that the eyepieces of Slit Lamp are correctly
focused.
• Set the brightness control of the instrument to position a low intensity.
• Set the illumination angle of the Slit Lamp to be approximately 60° to minimise unwanted
reflections.
• Insert the blue filter on the slit lamp beam path and fully open the slit diaphragm.
• Clean the doubling prism with Pantasept fluid at between 0.5% and 3.0% concentration
or with a similar disinfectant solution that is innocuous to organic glass (“plexiglass”).
After cleaning, rinse the doubling prisms in distilled water and allow to dry.
Clean and disinfect prism as described in Section 3 of this document.
• Place the doubling prism on into the holder and
align the ‘zero mark’ with the white alignment line
on the prism holder, this ensures the mires have a
horizontal split.
• Insert the measurement arm so that the
measurement head and microscope optics axes are
convergent.
• Rotate the measurement drum to position 1.

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KAT R Type and T Type Tonometer by KEELER
6.4 USING THE INSTRUMENT / TAKING A MEASUREMENT
Instructions to the patient
• The patient’s head must be firmly positioned on the chin rest and the forehead rest. If
necessary, a band may be used to hold the head still.
• Ask the patient to look straight ahead. If necessary, use a fixation target to keep the eyes still.
• We recommend occasionally reminding the patient during the examination, to keep his /
her eyes wide open. If necessary, the examiner may use the tips of his fingers to hold the
lids open, taking care not to exert pressure on the eye.
• When elevating the lids, the angle between the microscope and the lighting unit must be
reduced to about 10° so that the light beam passes through the body of the prism. In this
position it should be possible to obtain an image with no reflections.
• Immediately before measurement, ask the patient to close his / her eyes for a few seconds,
in order to ensure that the cornea be sufficiently wetted by the lacrimal fluid containing
the fluorescein solution.
6.5 TAKING THE MEASUREMENT
• Move the Slit Lamp forward to bring the measuring prism into contact with the centre of
the cornea in the area above the pupil. The limbus will be illuminated with a bluish light.The
examiner will be able to better directly observe this phenomenon from the opposite side.
• As soon as the corneal limbus is correctly illuminated, immediately stop all forward
movement of the Slit Lamp.
• After contact is established, observe the cornea
through the microscope. When the measurement drum
is set to position 1, the two semicircular fluorescein
rings (which will vary in size according to the ocular
pressure) will pulse rhythmically when the Tonometer is
in the correct position for measurement.
• Use the Slit Lamp joystick control to make any
corrections needed until the applanated surface is
observed as two semicircular surfaces of equal area
at the centre of the field of vision. (Figure 1). Small
adjustments downward made with the joystick will
have no effect on the sizes of the semicircular images.
• Increase the applanation pressure by rotating the Tonometer measurement drum until the
margins of the fluorescein rings touch and cross as the eye pulses (Figure 2). The width of
the fluorescein rings around the contact position of the measuring prism should be equal
to about 1/10 of the diameter of the applanation surface (0,3 mm).
Figure 1: Semicircular images at the
Centre of the field of vision.

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KAT R Type and T Type Tonometer by KEELER
• The LED reading is the ocular pressure expressed in mmHg.
7. PROBLEM SOLVING
7.1 THE FLUORESCEIN RING IS TOO WIDE OR TOO NARROW
Cause:
The fluorescein semicircles are too wide.
The measuring prism was not dried after
cleaning, or the eyelids came into contact
with the measuring prism during
measurement. The pressure reading is higher
than the real intraocular pressure.
Correction:
Move the slit lamp back and dry the
measuring prism with a wad of sterile
cotton wool or lint free cloth.
Cause:
The fluorescein semicircles are too narrow.
The lacrimal fluid has dried during
prolonged measurement. The pressure
reading is lower than real ocular pressure.
Correction:
Move the Slit Lamp back and ask the
patient to close his / her eyes once or twice,
then repeat the measurement procedure.
Figure 2: Correct Final Position

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KAT R Type and T Type Tonometer by KEELER
7.2 THE MEASUREMENT PRISM DOES NOT TOUCH THE CORNEA OR TOO
MUCH FORCE HAS BEEN APPLIED
Cause:
If the patient pulls his / her head back even
slightly, the pulses will become irregular
and the measuring prism contact with the
eye will become intermittent. If the patient
pulls his / her head even further back, the
fluorescein semi-circles will completely
disappear.
Correction:
If possible, use a band to hold the patient’s
head in place.
Cause:
If during measurement the slit lamp is
moved forward toward the patient or the
patient moves toward the slit lamp, the
sensor arm will be pushed into contact with
a stop spring and an audible alarm will
sound. The applanation surface will be too
large. The image will not change when the
measurement drum is rotated.
Correction:
Retract the slit lamp until regular pulses
and a correspondingly smaller applanation
surface are obtained. This is the correct
measurement position, in which variations in
pressure will not cause immediate variations
in the applanation surface.
7.3 THE TWO SEMICIRCLES ARE NOT CENTRAL IN THE FIELD OF VISION
Correction:
Using the joystick, move the slit lamp up
and to the left.

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KAT R Type and T Type Tonometer by KEELER
Cause:
The rings are too far to the right.
Correction:
Using the joystick, move the slit lamp to
the right.
Cause:
The reading in this position is considerably
higher than real ocular pressure.
Correction:
Using the slit lamp height adjustment
mechanism, lower the slit lamp until the two
fluorescein semi circles are equal in size.
The measurement pressure will then be
reduced.
7.4 THE INSIDE MARGINS OF THE FLUORESCEIN RINGS ARE NOT ALIGNED
AND TOUCHING
Cause:
The semicircular images are well centred.
The outer margins are aligned but the inner
margins are not.
Correction:
Increase pressure by rotating the
measurement drum.
Cause:
In this case, the inner margins of one
semicircle are aligned with the outer
margins of the other.
Correction:
Increase pressure by rotating the
measurement drum.

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KAT R Type and T Type Tonometer by KEELER
Cause:
Excessive pressure has been applied.
Correction:
Reduce pressure until the semicircular
images come closer together and finally
the inner margins align with each other, as
shown in the last illustration.
Correct final position
The inner margins of the fluorescein
semicircular images are aligned and
touching each other.
8. GENERAL INFORMATION AND SUGGESTIONS CONCERNING
MEASUREMENT
IMPORTANT NOTE
Measurement must be performed as quickly as possible on each eye. Should epithelial drying
be observed, we recommend the patient’s acuity and visual fields should be examined.
The pressure measurement procedure may be repeated several times. Nervous or anxious
patients often have higher intraocular pressure during the first measurement procedure.
It has been found that pressure decreases during the first few minutes of the procedure, when
the patient realises that the tonometric examination does is not unpleasant. When correctly
anaesthetised and with their eyes fully open, the patient will feel absolutely nothing.Therefore
we recommend running a preliminary measurement procedure on each eye, the results of
which need not be taken into consideration. After completing the preliminary procedure, run
three measurement procedures on each eye.These readings will be correct if the pressure has
stabilised. When the measurement procedures are performed correctly, the results of the
subsequent measurements will vary by only about 0,5 mmHg.
When the measurement procedure for one eye is prolonged excessively, a drying phenomena
will occur on the corneal epithelium of both eyes.
A ring of fluorescent deposits will form around the cornea contact surface and around the
measuring prism on the eye being examined. The other eye will show fluorescent dry areas,
resembling a map, which will hinder and make measurement unreliable.
The eye will rapidly recover from any corneal dryness without the need for any treatment, visual
acuity may be temporarily affected by fine epithelial defects.

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KAT R Type and T Type Tonometer by KEELER
9. ASTIGMATISM
If the cornea is spherical, measurements may be made along any meridian, but it is usual to
measure along the horizontal 0° meridian. This is not the case when measurements are made
on eyes affected by corneal astigmatism of greater than 3 dioptres, since the flattened areas
will not be circular but elliptical.
It has been calculated that in cases of more severe corneal astigmatism a surface area of
7,354mm2(ø 3,06 mm) must be applanated; in this case the measuring prism forms an angle
of 43° to the meridian of maximum radius.
For example:
For corneal astigmatism of 6.5mm / 30º= 52.0 dioptres/ 30º and 8.5mm/ 120º = 40.0 diopter
/ 120º, the 120° prism value will be aligned with the 43° “A” mark on the prism support.
For corneal astigmatism of 8.5mm / 30º = 40.0 dioptres / 30º and 6.5mm / 120º = 52 dioptres
/ 120º, the 30° prism value will be aligned with the 43° “A” mark. In other words, align the
axial position of the major radius (that is, the axis of a negative cylinder) with the prism value
at the “A” mark on the prism support.
10. ROUTINE INSTRUMENT MAINTENANCE
Keeler recommends this routine maintenance be carried out by the user
frequently to ensure safe and accurate measurement. In the event of
the device being outside of the calibration tolerances, it is important to
send the device back to Keeler Ltd. or your local dealer for repair and
re-calibration.
43° marker
0° marker