PROTECT: Protect your hearing from damage due to loud noise COMFORT: The Razor series feature Walkers new comfort fit headband for all day shooting AUDIO INPUT: The electronic muff features a 3.5mm audio input jack for use with iPods, MP3 players and handheld radios VOLUME CONTROL: The Walkers Razor Slim Electronic Muffs feature an on/off and volume knob with raised ridges so you can adjust even while wearing gloves LOW PROFILE: These 'Razor' thin muffs were engineered from the ground up with the goal of having the lowest possible profile without compromising the hearing protection and amplification properties of the muff.