BDN6731A BDN6731 - 2-Wire Surveillance Kit with Extra-Loud EarpieceBDN6731A BDN6731 2 Wire Surveillance Kit with Extra Loud Earpiece This earpiece allows the radio user to privately receive messages and is ideal when environments require discreet communication. This black, 2 wire earpiece has a separate microphone and Push to Talk feature, and its intrinsically safe. It also includes an extra loud earpiece, which exceeds OSHA limits. It requires a 3. 5mm threaded audio adapter, unless being used with a speaker