Manufacturer product description:
Alvis Mk5, advantages:
Enhanced attenuation of medium and high frequencies: + 6dB and +5dB noise attenuation in relation to the Mk3, or 4 times more protection.
Open position offers high hearing accuracy,
Shut-off valve offers 2 noise attenuation levels,
Effectively filters sounds without distorting them, human speech is easy to understand,
Quick and easy to put in, stays in place in your ear,
Ultra-comfortable, can be worn all day long.