Two Antique Glass Telephone Insulators Lot of two telephone insulators, one large and one small, made by Hemingray. The larger insulators were usually used for power and phone lines, while the smaller insulators were usually for telegraph lines. These insulators are from the 1940s, and are in relatively good shape with any chips or cracks displayed in the photos. Approximate size together: 6" x 4" x 3.75" Approximate weight together: 2.25 lbs