Solve the problem of having to run wires with STI’s commercial-grade wireless musical chimes. Quick and easy to install, they require no electrical wiring and no expensive through-the-wall drilling. All units offer an exceptional operating range of up to 500 ft. between transmitter and receiver — making it the longest range plug-in chime in the industry, according to STI. Select one of 10 sounds with the push of a button. Because they are compatible, numerous transmitters can link to the same receiver. Distinguish between front and back doors by selecting a different sound on each. Features include UL/cUL listed, FCC certified, and 433 MHz operation. Four models are available: STI-3350 wireless doorbell, STI-3360 wireless entry alert chime with receiver, STI-3610 wireless motion-activated chime with receiver, and STI-3300 wireless doorbell extender with receiver.