Swartchild CLOSED LOOP Clock Mainspring - 3/16" x .013" x 24" Long

Swartchild & Co. Clock Mainspring, CLOSED LOOP End – 3/16″ Width, .013″ Strength/Thickness, 24″ Length, steel, new in package. Yes, the envelope says something different but the correction to 4.80mm wide is accurate, and the width does measure 3/16". I have yet to find a clock that uses this mainspring but it was undoubtedly made for a small clock.  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.