To ring the doorbell all one has to do is grab the clapper chain and swing the
clapper to sound the cast blue bell. An electronic circuits detects the clapper
movement and sends a radio signal to the indoor doorbell.
Size:18" high (including chain) x 5" left to right x 5 1/2" deep.
Materials used for this project:pine, brass, cast bell and bracket, reed switch and magnet, transmitter circuit board.
Cost: included with purchase of any Doorbell.