Motorola RAN4031A Pair of Replacement Antennas RDU4100

These are Motorola RAN4031 antennas, supplied as a pair. Motorola's RDx Series user guide lists the part in its antenna table as a UHF whip antenna for 438 to 470 MHz.

The frequency range is the specification to match, and it is narrower than people expect. A UHF radio programmed outside 438 to 470 MHz will physically accept this antenna and quietly lose range, which is why the band appears in the part description rather than in a footnote.

The whip is the longer shape. Motorola lists the RAN4033 stubby at 450 to 470 MHz in the same table as the shorter option, and the RAN4041 helical for VHF at 146 to 174 MHz. Supplied as a pair.