The object is an empty rectangular box meant to hold five fuses. It was found with the Off Line Selectric Analyzer, which has two fuse holders, one of type 3A and one of type 2A..
Des Plaines, Ill.
||Stamped on the side of the object
overall: 5/16 in x 1 1/2 in x 1 1/4 in
Gift of Dave Babcock