Swartchild Black Shield Clock Mainspring 3.4 x .23 mm x 21¼" Ref 34-23 C 54

Swartchild & Co Black Shield Clock Mainspring, Tongue End, for Kienzle 31 / 171, 31/172, 31 / 173 & Muller 39/75, Solo 74 TIME side only, GR Ref. 34 - 23 C 54, steel, made in France. See images for precise mainspring specifications. I specialize in hard to find watch & clock parts and all parts are unconditionally guaranteed. Images do a pretty good job of representing the item