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.
80mph speedo in mint condition. it has a fitting on drive shaft thats screws on. it can be removed with one screw making it normal . email if you need more info.