1Fitmrnt: The Dtmf microphone is a replacement for Ft?7800R Ft?8800R Ft?8900R Ft?1802M Ft?1807M Ft?2800M Ft?2900 Ft?1907R. 2Function: Used for liaison and command dispatch between group members, improving communication efficiency and response ability to deal with emergencies. 3Feature: Windproof designed specifically for windy outdoor environments. The noise canceling audio optimizes your sound in noisy environment. 4High Performance: High efficiency of sound transmission, low distortion, fast response, smooth communication, sensitive, to ensure efficient calling. 5Easy Installation: Installation is quick and easy, can be replaced directly, and can be installed without modification, saving time and energy.