I forgot to post a picture of this corona ring I found last month when I walked the NS Port Road near Marietta PA. The PRR used these on their 138kv 25hz transmission system in place of lightning arrestors, and they are usually located on the the transmission poles right at the substation bringing the transmission line in. Another set is also placed about 8 poles away from the substation. This one is a bottom ring, with the conductor shoe going where that clevis is. I found others there but they were so mangled they weren't worth saving.