A 6.75 inch green porcelain suspension from Germany with the small 7/8 inch ball. Also uses the W shape locking pin.. A marking in the porcelain is obvious but undecipherable. . The closeup shows the cap marking. The reverse is stamped 1713. A second cap has a different mark on reverse but is hard to see, two crossed T 's inside a circle. .Fredrik Hojefalt has identified that this suspension insulator is made by Porzellanfabreik Teltow in Holenbrunn (Oberfranken) in Germany. As for the mark on the other side, I have no idea. Possibly it is the mark of the supplier of the cap itself?? From Zoltan's homepage I find " Teltow, Porzellanfabrik Teltow GmbH Teltow bei Berlin, Germany"