This will work for any round, 3/4" rocker switch and a standard 1/2" cable gland. The fit for the cable gland may be tight depending on how much contraction you get upon cooling. There is not much room to make this slimmer, but depending on your use, it could be at least half the length it is.

The use case for this is as a remote control for an astronomical observatory dome using a Maxdome II control card from Diffraction Limited.