Comsco Mainspring #1158 for Illinois 6s & 4s movements Factory No. 47354 - Steel

Comsco Mainspring #1158 for Illinois 6s and 4s movements Factory No. 47354, Steel. See image 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.