SadoTech Model CX Wireless Doorbell with One Receiver and Dual Transmitters Operating at 500-feet Range with Over 50 Chimes, No Batteries Required for Receiver, (White)
A doorbell that includes two transmitter buttons that can trigger (ring) a single chime unit.  Perfect for those that have two rooms or entry doorways and want a single chime unit to be activated when either of the two transmitter buttons are pressed.   (Note: The chime units can only be configured to ring with the same melody/ringtone for both transmitters.)