Repair Tools Watch Mainspring Winder Replacement Barrels for 3135/2836/8200 Movement. Made of high quality material, durable, practical. Scope of application: home, watchmaker. For Clock Key Winder Mainspring. 14×8.6×6.1cm/5.51×3.39×2.40inch. 1Set Watch Mainspring Winder. Please allow slightly difference due to manual measurement. Color may be slightly different since different monitor.