This is another one of my favorite wire holders. These were mades for the Spero Electric Corp by some porcelain manufacturer. Most are not marked or have the bottom rusted so much you can't see the embossing. You can't see it too well in my picture but the later pieces were marked on the bottom around the lag Spero/ Cleveland. I have assembled several different pieces and went through a lot to find ones with the embossings visible. On my display you can see the pat. no. 2,081,832 which is for the three lags on the end with a screw holding on the lag. I think these were made by ceramic Specialities Company for them. They had another patent 2,158,012 which was for the pressed metal bottom and lag. They could have made these as well being both companies were located in Ohio. In my picture from left to right: Small one marked 1408 (cat No.), Next two marked Cleveland U.S.A./ Spero 710, Next marked 2081832 (pat No) other side unreadable, Next marked Pat Pend on front 1410 on back. Middle small No Name, Next is more modern one in white No Name, Next Lt. Brown has Pat Numbers/, The last three have Pat 5,25,37/ No. 2.081.832 recessed embossed on the bottom. The bottom row is a dark brown No Name, Bottom showing Spero/Cleveland, Another Spero 710 and a different light brown one. Really neat pieces.