These ear plugs are equipped with a revolutionary and innovative flat attenuating filter for a very wide sound spectrum (125-8000 Hz).
Sound is attenuated at all frequencies by 15dB (ER15) specially recommended in situations where it is essential to retain the timbre , for example in the case of musicians, amateur and commercial pilots, and countless industrial situations.
ER25 filters are also available providing 25dB attenuation.