This set of three CD 121 glass insulators is a must-have for any collector of vintage items. The insulators were manufactured in the United States, aqua c d & p tel with a base chip flake and a dome fisheye ding.  Lt. blue aqua Am Tel & tel Denver Mold couple pin hole dings, and dark aqua Am Tel & tel. small base chip flake. insulators can be used in a variety of ways, such as for decoration or as part of a DIY project.