Features a 360-degree swivel mounting plate attached to a double wheel roller system. Two-hole, metal flange-mounted ball bearing resting on individual support bearings, ideal for most industrial transfer applications. Ball transfer unit can also be used in various non-industrial applications, including retail store displays and airport luggage handling systems. Ball support cup is hardened and plated; protective cover ensures low torque operation. Suitable as a replacement for damaged ball casters in office chairs and similar equipment. Specifications: Surface treatment: Zinc plating Model: 15A Length: 50mm Width: 32mm Mounting hole pitch: 40mm Fixing hole distance: 4mm Single load capacity: 10kg (Max 15kg) Color: Silver Material: Carbon steel Size: Ball diameter: 5/8 inch (approximately 15.8mm), height: 21mm Package Contents: 5 x Roller ball transfer bearings Note: Light and display differences may cause slight variations in color between the image and the actual item. Measurement allowance is +/- 1-3cm.