The Curtis Jack Switch 1TBP100 for a Curtis Sno-Pro 3000. There is also a boot available: 1TBP100A. This mounts in the A-frame. There is a jack switch adapter for the plug harness also available. This has 6 tabs on the bottom.
The markings on the switch are "10.1A 125 VAC 1446 T7-20020 OTTO".
Below is a diagram for the Jack Adapter if you have the 2-plug wiring harness: