Eightwood 2pcs Handheld CB Ham Radio Antenna Adapter,SO239 to BNC Female RF Connector Connector 1: SO239 female | connector 2: BNC female Brass (Not Alloy) material ensure higher signal transmission and connectivity Adapter with nickel plated for durability and repeated disconnects Impedance: 50 Ohm Package includes: 2pcs SO239 to BNC handheld radio antenna adapter