The Shure UABIAST is an in-line adapter that supplies 12V DC bias power over coaxial cable.

Compatible with the UA874 active antenna and the UA830 in-line antenna amplifier, the UABIAST allows those accessories to be used with Shure wireless systems that do not supply power from their BNC antenna inputs and are used without an antenna distribution amplifier. One UABIAST supplies power to any combination of up to three connected accessories for extended cable runs and antenna placement options.