57 Chevy Electric Windshield Wiper Motor Slide.
The slide mounts to the top of the wiper motor and the wiper cable attaches to it. The slide turns the wiper motor on and off. Since these under-the-hood connections are plastic, they are prone to heat deterioration and discoloration. Don't let them break unexpectedly. This is a low-cost item that should be replaced regularly. Made in the USA.