Not tested, but guaranteed to work for 2 prong electric machine.  Cord looks to be in good condition. Lever clicks as expected.

There is no name plate, manufacturer, or model number, just an "SA" in a circle.

The 2 prong plug goes into your wall outlet.  Your machine then plugs into the receiver on this switch.  Note the receiver has 3 slotted opening marked 1,2,3.  Be sure to look at that photo.

Let me know if this doesn't work and I'll refund you promptly.