USR Mainspring for N.Y. Standard 18s No. 2189 - Steel

USR Mainspring for N.Y. Standard 18s movements, Factory No. 2189, HOLE end, steel, new in envelope. This is marked No. 925 which is curious as I don't see than number ever being used, and I'll also note that the strength of these Standard mainsprings can vary widely so I checked this one and it has a strength of 0.23 so this will work nicely down to a 7j. I likely have several of these so the one you get may differ slightly from the images. I specialize in hard to find watch parts and all watch parts are unconditionally guaranteed. Images do a suitable job of representing the item