Features: Precise engineered watch mainspring winder replacement barrels ensure accurate coil maintenance for 10 type mechanical movement. Use selected 304 stainless steel and brass, this 10in1 set features anticorrosion barrels specifically size for watch repair and adjustment. Great for horologists, watch enthusiasts, and professional repair technicians requiring movement specific tools for vintage timepiece restoration. Simpify watch servicing tasks in workshops, home studios, or boutique stores while maintaining original movement integrity during mainspring replacement. Each barrels calibrated dimensions ensure secure compatibility with 10 type movements for flawlessly winding performances. Specifications: Product Dimension: As pictures shown Component: Stainless Steel, Copper Package Includes: 1 Set Watch Mainspring Winder Kits note: Please allow 1-2cm errors due to manual measurement. Due to the differences between different monitors, the picture may not reflect the actual color of the item.