This next picture is of wire holders all made by Colonial Insulator Company based in Ohio, All the pieces except for two have there C I within a circle marking on them somewhere. The company marking that I can't identify is the L within a diamond. It was obviously a decent electrical or related company due to the number of pieces I've found and were deeply tied to Colonial Insulator Company marking them. There insulator designs are unique and you would think I could find patents on some of them. I've had no luck so far matching a company with this marking. In this picture is some of the wire holders with these markings. The first two are just marked with the C I in a circle, The next has the Diamond L marking and A-65 with the C I marking below it. The next bigger style has the diamond L and on the back A-64 and C I marking below it. The one next to that has a slightly modifided diamond L marking with A-126 on the back, Next has no markings and the last is marked modified diamond L and on the back A-44 with C I marking below it. On the bottom is another diamond L A-64 with the large lag. If you have any leads or pics of ones you have I'd love to see them.