Small bakelite on-off switch.
This is an English made switch and is spring-loaded in the closed position. The circuit shorts out when pulled out.
The diameter of the knob is 1/4" and 7/16" long. The overall length of the switch is 3".
I can send more photos on request, and I accept PayPal.
Broken down. Not working. Could bake a working engine from the 2. Found in grandfathers / uncles garage along with large amount of other de Dion parts..