Each XP3 ear plug has a built in acoustic filter and a stopper. With the stopper open, XP3 will allow sounds below 80 dB to pass through easily, so you can hear game in the field when hunting, road sounds while riding your bike in the city, the full range of music at concerts, and voices in noisy environments. With the stopper open, the level of acoustic resistance varies with the noise level: the louder the noise, the more it attenuates the sound, providing you with just the protection level you need in many different noise situations.
With the stopper closed, XP3 provides a constant NRR 24 level of noise protection that is ideal in many industrial environments, in the workshop at home and for indoor shooting.
The low profile of the XP3 means you can wear these comfortable form fitting ear plugs under helmets, with hats of all kinds and even while sleeping.