Challenger II Racing Foam Ear Bud Speakers with 1 8" Mono Plug prerunner AlphaBass Headset Features:• TRUE Carbon Easily expand to your 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 managing a team on a job site Utilizing a hearing aid transducer instead of a standard speaker expect unmatchable clarity from these earbuds