For use with Power Acoustik(R) Mobile A/V systems; Earpads fold flat for seat pocket storage; Channel selectable from each headphone; Adjustable headphone straps for comfort; Auto mute control; Variable volume control; Auto level control; Auto power-off function; On/off switch saves battery life; MP3 player input via 3.5 mm input; Includes 3 AAA batteries and EVA hard carrying case;