Rear Seat Expansion Kit with Helmet Kits or Headsets Select Helmet Kit or Headset:Ultimate Headset Behind the Head RUR MLA 1001 Helmet Side Only of Laser cut gasket RUR MLA 1001 Helmet Side Only of the MagLock Helmet Air Kit Use the front button to play and pause your music as well as answer and disconnect phone calls AlphaBass Headset Features:• TRUE Carbon fiber in AlphaBass models • Leather ear seals• Flex Boom Mic• M101 Red dynamic noise cancelling mic• Easy to use volume and bass controlUltimate Mono and STX Headset Features:• Carbon Fiber style finish• Flex boom mic• M101 red dynamic noise cancelling mic• Hard wired cabling• Large comfortable gel ear seals• Cloth ear covers• Easy to use volume controlMono and STX Helmet Kit Features:• Alpha Audio speakers • Superior highs and lows for quality sound• Clear Hear speakers• Dynamic Noise Canceling mic• Easy to install Helmet speakers with peal and stick adhesiveIncludes:• (2) Headsets or Helmet Kits• (2) 16' intercom CablesCompatibility:STX: Works with STX STEREO High Fidelity Intercom (see compatibility info below)