The smooth, level dependent function in these Peltor muffs eliminates abrupt sound cut-off and protects against harmful impulse noise while letting in, and even amplifying, ambient sounds. •Smooth level dependent function, which eliminates abrupt sound cut-off •Interchangeable shells makes it easy to change colour •A pair of red and black shells included •Collapsible for easy storage •Audio input for external radio •Input jack allows you to connect to selected 2-way radios or other electronic audio devices •Water resistant exterior