Galvanized Smooth Operation Roll up Door Accessory Spring Box with UL Listed

Galvanized Smooth Operation Roll up Door Accessory Spring Box with UL Listed. Integrated Steel Ball Bearing: Ensures ultra-smooth, whisper-quiet movement with minimal friction. Anti-Corrosion Galvanized Steel: High-grade material with 0.8-1.2mm thickness for long-lasting durability. Multiple Size Options: Outer diameters 200mm, 220mm, 240mm; Inner holes 50mm, 60mm, 76mm. Precise Shaft Fit: Designed for 60mm (2.4') and 76mm (3.0') steel shafts. 1-Year Warranty: Comprehensive coverage for mechanical defects and quality assurance. Online Technical Support: Professional assistance available for installation and maintenance issues. Universal Application: Suitable for manual and motorized roller shutters and garage doors. OEM & ODM Services: Customizable sizes, materials, colors, and designs to meet specific needs.