Rail adapter compatible with all helmets with ARC rails on the sides Arc rail adaptor version, compatible with arc rail side helmet, can be attached to the rear of the ear when airsoft headphones are not required, providing ear rest. With 360 rotated design, will be easy to adjust possition of comta headset. With two pickup microphones on the left and right, the electronic automated sound pickup function, the ear defender will supplement the ambient sound, such as foot speech, rather than completely isolate the external sound. Tactical headphones are ideal for tactical games, airsoft sports, shooting games, or anyone who needs to communicate in a noisy setting. Hearing protection will protect against sudden sound of guns and explosion. and automatically turn off pickup function, effectively reduce ambient noise,USE 2*AA batteries (not include).