[Ron Ramirez]

This set, along with all of the larger 1937 Philco chassis, were originally held in place with J-bolts; the "J" end was hooked over each of those four studs protruding from the sides of the chassis and then the bolt passed through the wooden support, secured on the other side of the wood with a washer and nut.

These J-bolts were only intended to be used in shipment; they were supposed to be removed when the set was installed in the customer's home, leaving the chassis supported only by that one small bolt you pictured. In this manner, the chassis could float freely on the gum washers surrounding the holes in the wood through which the J-bolts passed.

Occasionally, you find a large 1937 Philco console in which the chassis still has its J-bolts, but usually not. This is how I discovered that Philco used these - I once owned a 37-116 that still had its original J-bolts.