Newall SUPER Security Mainspring #614 for 16s Hamilton 534B / 718050 - Alloy

Newall SUPER Security Mainspring #614 for Hamilton 16s 21 Jewel Movements, Factory No. 543B / 718050, alloy, new in envelope. See images for precise mainspring specifications. I likely have several of these so the one you get may differ slightly from the images. I specialize is hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a pretty good job of representing the item.