1.Advanced Nipple 2 pin Acoustic Tube Covert Earpiece Earphone Headset PTT(Push To Talk) with built-in line mic microphone PTT for Motorola Radio Security Door Supervisor 2pin. 2.Excellent for use in FBI, Bodyguard, police, military, nightclubs, bars, paintball, security, restaurants, hotels, bouncer, warehouses, and noisy environments