The HM 100 full face helmet headset and PTT system is an accessory for use with handheld 2 way radios (e.g. PMR446 GMRS CB amateur commercial). The HM 100 makes the use of a 2 way radio convenient and safe while riding a motorcycle snowmobile ATV or any other activity in which a helmet is worn. Use the HM100 in conjunction with your 2 way radio for bike to bike sled to sled and ATV to ATV communications while riding. The HM 100 features a full face helmet headset with 2 ultra thin speakers and microphone that attach quickly and easily inside the helmet. A weatherproof handlebar mount push to talk (PTT) switch puts control of the 2 way radio at your fingertips. Generous cable lengths and helpful accessories make installation easy and professional looking.