M51 Tactical PTT ICOMDescription Conceived and manufactured by Earmor, the M51 Tactical PTT ICOM is an external PTT module designed for dedicated active and communication headsets. Made of high quality polymers and metal alloys, M51 Tactical PTT gives the option of simple and effective communication without the need for constant operation of the handheld radio. An additional buckle provides an easy way of attaching the PTT to any place on used gear. Compact size and