Heath Zenith White Plastic Wireless Door Chime Extender

This doorbell extender works by listening for your existing doorbell to ring.  When it does, the transmitter sends a wireless radio signal up to 100 feet to the plug-in door chime receiver. The unit is simple to install. Simply place the extender's transmitter on top of your existing chime and then plug the receiver into a standard wall outlet. The extender module uses 4 AA batteries (sold sepetately) and measures 1.97W x .63D x 5.94H. The White plug-in chime features three selectable sounds with adjustable volume and measures 3.48W x 1.42D x 12H.