This is an adaptor to convert the SMA 'screw on type' aerial output socket of a transceiver / receiver or scanner to a BNC type plug or aerial.
Fits hand-helds such as the TYT MD-380, Icom IC-R5, IC-R2 Yaesu VX-5, VX-2 (Will not fit Yaesu VX-7R Maycom AR-108 or FR-100)