This FA205D is a new wireless double-button belt clip transmitter works with the FA400 Series Receivers, models FA401, FA404, FA416 or FA464, that operate on 900MHZ (Receiver not Included) the transmitter is not weatherproof. this unit can also be mounted under a desk by removing the belt click and securing it under desk with 2 screws, this transmitter can also be converted to pendant by removing the belt clip and attaching and optional loop chain, (not included) please be aware this units have been sitting on my shelf for some time, although the battery is included, I would suggest to install a fresh battery (CR 2 Lithium).
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