This premium speaker system brings you flawless audio integration on and off the mountain with all 2010 and 2011 RED adult helmets. The 40mm drivers plug-and-play into helmet ear pads while the 57mm drivers work in both the helmet ear pads as well as RED’s premium DJ headset. REDphones are compatible with iPod® or other music players and feature on-cord volume/mute control. NEW for 2011, REDphones Premium include Smartphone cord with inline audio controls.