
SKU 66452 For technical questions, please call 1-800-444-3353. Page 2
Use as intended only.4.
Inspect before every use; do not use if parts5.
loose or damaged.
Maintain product labels and nameplates.6.
These carry important safety information.
If unreadable or missing, contact Harbor
Freight Tools for a replacement.
Instructions
Adjust the band to proper position.1.
Pull hair out of the way and out from beneath2.
the muffs.
Adjust the height of the cups so they fully3.
enclose the ears and the cushions press
equally around the ear. Put the ear muff with
the controls on the right ear.
It is important that cushions seal completely4.
around the ear.
Always wear ANSI-approved safety glasses5.
when working with tools and equipment.
When using these ear muffs with safety
glasses, the safety glasses must have thin
temples that t closely around the head or
thin straps; this will help ensure a good t
and better protection.
Press the black power button located above6.
the control dial to activate the radio. Press-
ing the button again will toggle to listen
mode, allowing you to hear outside noise.
Turn the dial clockwise to raise the radio7.
volume. The dial can also be used to turn
off the radio by turning it all the way counter-
clockwise until the power “clicks” off.
Press the SCAN button to toggle through8.
radio stations.
Press the RES button to reset the scan at the9.
bottom of the FM dial.
For MP3 access, plug cord into outlet at bot-10.
tom of right earmuff.
Replacing Batteries
Turn off the Ear Muffs.1.
Insert a coin or large at-edge screwdriver 2.
(not included) into the slot at the bottom of
the left ear cup and pry off ear cushion.
Remove the outer foam, exposing the two AA3.
batteries.
Remove old batteries and replace with two4.
new AA batteries, making sure to install ac-
cording to indicated polarity.
Replace outer foam and snap ear cushion5.
back into place.
Noise Reduction Rating (NRR)
Record Serial Number Here:
Note: If product has no serial number, record
month and year of purchase instead.
Note: Replacement parts are not available.
The EPA has selected the NRR as the measure of a
hearing protector’s noise reducing capabilities. Harbor
Freight Tools makes no warranties as to the suitability
of the NRR as a measure of actual workplace
protection since such protection is highly dependent
on user training, motivation, and utilization. A better
estimate of workplace protection can be obtained by
derating the labeled NRR by 50%.
The NRR calculated from this attenuation data is 26.
Improper t of this device will reduce its effectiveness in
attenuating noise. Consult instructions for proper t.
The level of noise entering a person’s ear, when a hearing
protector is worn as directed, is closely approximated by
the difference between the A-weighted environmental
noise and the NRR.
ATTENUATION DATA ANSI S3.19-1974
Test
Frequencies (Hz) 125 250 500 1000 2000 3150 4000 6300 8000 NRR
Mean
Attenuation (dB) 9.0 19.8 31.0 34.8 36.4 38.3 39.1 40.9 37.7
27
Standard
Deviation (dB) 2.9 5.4 5.4 4.8 3.7 3.7 3.0 3.7 3.7
Example:
1.)Theenvironmental noise level as measured at theearis 92
dBA.
2.) The NRR is 26 decibels (dB).
3.) The level of noise entering the ear is approximately
equal to 66 dBA.
CAUTION! For noise environments dominated by
frequencies below 500 Hz, the C- weighted environmental
noise level should be used.
The NRR used in the above example was achieved under
laboratory conditions.
Although hearing protectors can be recommended for
protection against harmful effects of impulsive noise,
the Noise Reduction Rating (NRR) is based on the
attenuation of continuous noise and may not be an
accurate indicator of the protection attainable against
impulsive noise such as gunre.
REV 08l