RN Mainspring No. 209 for Gruen 430, 431, 435, 440 caliber movements - Steel

RN No. 209 mainspring for Gruen caliber 430, 431, 435, 440 caliber movements, steel, new in envelope. See images for mainspring specifications. I specialize in hard to find watch parts so I usually have whatever you might need and all watch parts are unconditionally guaranteed. Images do an adequate job of representing the item.