The U-945 porcelain insulator is marked with the Mershon patent date and was most likely made by Thomas. The CD 288 shown is known as the "Triple Ridge" which matches the Mershon patent drawing. It was most likely made by the Valverde Glass Works in Denver, CO under Robert Good Jr. In "Dreams of Glass" William McLaughlin recalls working in Robert Good's factory on a large power piece they were having difficulty making - most likely the CD 288.