Seth Thomas Mainsprings

Welcome to Cas-Ker's page of Seth Thomas Pocket Watch Mainsprings! Cas-Ker has Seth Thomas Mainsprings and other Seth Thomas pocket watch parts. We carry thousands of pocket watch, wrist watch, and clock parts.

Experience the best service in the watch material business. We carry all available brands of watch material including crystals. For fast and efficient service, send your next parts order to Cas-Ker, where material is our main business.

Click "View Options" or the Product Name to view mainspring factory numbers, sizes and strengths.

Cas-Ker Co.
2550 Civic Center Drive | Cincinnati, OH 45231 | CALL 800-487-0408 | FAX 800-487-5848 | Cincinnati 513-674-7700