Dakota Alert MURS Wired Doorbell Ring Detector, White (MURS Chime) The MURS Chime is an auxiliary chime that can be connected to the M538-BS base station transceiver Plays one of three tunes (Westminster Chime, London Bridges, or Oh, My Darling) when the base station receives a signal from the MURS Alert transmitter Features volume control and operates on two AA alkaline batteries (not included)