The Bifrost Gear COM-RAC for Comtac allows operators to easily convert their Comtac or clone headsets to work with the Ops-Core AMP Helmet Rail Mount Kit (RAC Arms) Features: Converts OPS-Core AMP arms to work with Comtac Headsets and Earmuffs Allows headsets to attach to rear dovetails on ARC rails Installs in seconds, no modifications to OPS Core AMP arms or headsets required Compatible with the following headsets: Comtac II / III / V / VI, Z-TAC C2 & C3, WADSN, most clones. (Includes one pair of adapter brackets; OPS-Core AMP Helmet Rail Mount Kit and headset not included) US and International Patents Pending