This is an OEM TTI microphone, similar to the one which comes in a box with these radios.
AMC-5011: TTI 4 pin replacement microphone for TTI TCB550 / TCB550N / TCB560 and TCB555 CB radio models. It will also fit the midland 210DS radio.
AMC-5020: Original replacement microphone for TCB1100.
AMC-5021: Genuine replacement 6 pin TTI microphone, will fit the following radios TCB660, TCB770, TCB771, TCB880, TCB881, TCB900, TCB1100.
We also supply a Non-OEM Sharman’s microphone for these radios. Please see our product code MP-520P2.