Mooney M20A and possibly M20B M20C D E F & G Throttle Warning Micro Switch Early 60s And Probably More. This was firewall mounted in early Mooneys before they moved to close to the throttle behind the control panel.

This switch activates the gear warning horn if the throttle is closed before the gear is lowered.

Possibly used in Piper Cessna Beechcraft and for sure good fo Experimental and homebuilt aircraft.