With Audio customization, the Crusher Evo analyzes your hearing and produces sound specifically for YOU. Adjust the bass with a slide to produce bass you can feel! 40 hours of listening off of 1 charge. Boost your bass with the bass slider, mellow out or go all in skull-crushing! The Crusher Evo achieves a level of comfort through a thick padded headband and foam cushion ear pads and uses the integrated hidden mic for calls.