vintage Crouse-Hinds explosion proof enclosure, industrial iron push button switch box

Vintage Crouse-Hinds industrial cast iron electrical box for a push button switch. We've been told that this is an explosion proof enclosure. It is marked F31 Conduit on the back.

This electrical box measures about 4 1/4" long (5" overall) x 2 3/4" x 2". It is made for conduit mounting and is about 3/4" across the threaded mounting.

We have not tested the old push button switch.