BESTFIT Clock Mainspring suitable for Emes Bavaria, Borletti 300 - H500-1

Bestfit System #77 Clock Mainspring suitable for Emes Bavaria, Boreltti 300 clocks and perhaps others as well, HOLE end, No. H500-1, 1940's or newer, steel. See images for precise mainspring specifications. I specialize is hard to find watch & clock parts and all parts are unconditionally guaranteed. Images do a pretty good job of representing the item