Switch, rotary enclosed, Four Pole, Single Throw (4PST), ON-OFF-ON-OFF, 10 Amps, 125 VAC, Submersible to 15 feet. Type 1SR4A4-2 in a 4" round brass enclosure. Part Number M15743/4-001 per MIL-DTL-15743/4. NSN 5930-00-259-7368. This highly versatile switch can be used to switch a single 3 phase load, two single phase loads from two different supplies, etc. Get creative.