Alloy Mainspring for 16s Hamilton No. 534B / 718050

Unmarked Maker but likely Swiss Made Alloy Mainspring for 16s Hamilton, Factory No. 534B / 718050 for 992B & 950B, new in 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.