The item for sale is a

Motorola BDN6676D Audio Adapter

New, genuine OEM. 

Radio models compatible with this adapter:
GP900, GP9000, HT1000, JT1000, MT2000, MTS2000, MTX8000, MTX838, MTX900, MTX9000, MTX960, MTX LS, XTS1500, XTS2500, XTS3000 and XTS5000

EF Johnson models compatible with this adapter:
5100 SERIES, 511X, 512X, 514X, 518X, 51SL ES and Ascend ES