The Modular Attached Rail Kit (MARK) 2.0 allows the end user to seamlessly integrate their hearing protection and/or integrated communications into their headborne systems and improve the consistent seal of ear protection. The MARK 2.0 is compatible with most major helmet types and the most popular electronic hearing protection. The MARK 2.0 Kit will work with 3M Peltor(TM) Headsets right out of the package. If attaching to Sordin/MSA(TM) style headsets, use the SARA Adapters (sold separately). The MARK 2.0 Kit comes with all hardware for attachment to Ops-Core ARC(TM) (and similar) and Team Wendy EXFIL(TM) Gen 2 and 3 rails. An M-LOK(TM) Adapter Kit is sold separately Mfg: Unity Tactical