The item shown on the left of the picture is made by Pass & Seymour. I believe it to be one of the earliest fuse cut-out styles made by this company, predating the white 1899 patent dated model in the next picture. The model number is not included on this unit, as perhaps the company had not considered style or model numbers being required.

Note the shiney band around the neck of the unit. There was a metal collar used to hold the unit in place. Future models / styles had bolt holes to mount the units.