Comsco Mainspring #1222 for 6s N.Y. Standard Factory No. 727 / 5134 - Steel

Comsco Mainspring #1222 for 6s N.Y. Standard movements, Factory No. 727 / 5134, Hole end, steel, new in frail envelope. See images for precise mainspring specifications. I specialize in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.