Here is a few other interesting items I have. The top one is a porcelain tree line protector made by PINCO. Mine measures 16" but they had different sizes. They are very heavy and would do the job but were replaced by heavy duty plastic line covers. The bottom two insulators are Fargo porcelain line splices. They are unmarked but were sold by Line Material Co. They have a spring in the ends which would hold the wire when pushed in. There are access hole to push the spring to release the wires. I have never seen these in use but they had differentd sizes although these sizes are the ones I've always seen. Would think they would be heavy on the lines as well.