RETEVIS M Throat PTT Covert Acoustic Tube Earphone Speaker Microphone 1. This is an ideal choice for use in high environments, such as driving, riding a motorcycle and bicycle. It is also ideal for surveillance purposes and airport security, casino security, crowd control for conferences and concerts, and other work environments that require careful communication. The throat microphone is also easy to hide under the collar. 2. A remote microphone with a push-to-talk button, you can edit anywhere. 3. The microphone emits sound directly from your throat, so it is not sensitive to background noise. 4. Have the highest quality transparent sound tube that is almost imperceptible to people around you, which can protect your body from radio electromagnetic wave radiation. 5. Spacing between two needles: 8mm 6. Two-pin standard diameter: ear 2.5mm stereo (thimble). Microphone 3.5mm stereo (bottom pin) 7. Weight: 50 grams 8. Suitable for CLS series CLS1110, CLS1410, CLS1413, CLS1450, CLS1450C, CLS1450CB, VL50, suitable for XTN series XTN446, XTN500, XTN600, suitable for GP series GP2000, GP2100, GP300, GP308, GP68, GP88, GP88S, suitable for P series P040, P080, P1225, P1225LS, suitable for FDC FD-150A, FD-450A, FD-160A, FD-460A, suitable for RDX series RDV-5100, RDV2020, RDU2020, RDU2080DD, RDU4100, RDU4160D, RDV2080D, RDV5100,etc