Product Material: galvanized iron colorsilver Ball material: nylon Ball diameter: 16 mm 0.5Inch 25 mm1Inch 16 mm dimensions: 48 x 32 x 20 mm (L * W * H) 25 mm dimensions: 75 x 50 x 30 mm (L * W * H) Package includes: 4 x roller transfer 8 x screw 1. DELIVERY CONTENT: 4 x nylon furniture casters, 1 x screwdriver, 8 x screw, 16 / 25mm diameter round ball transfer, the space for installing the transfer bearing roll is small. There are two mounting holes for screw mounting. 2. HIGH QUALITY MATERIALS: The main body of the ball transfer unit for furniture is made of galvanized carbon steel, which has the properties of scratch resistance, corrosion resistance, rust resistance, and is not easy to damage. 3. COMFORTABLE AND PRACTICAL: Smart and trouble-free; The ball can rotate 360 degrees flexibly, use it smoothly, move goods faster and save more time. The maximum load capacity of a single caster is 15 kg, which is applied to most objects. 4. NO NOISE: The transfer units of the roller ball bearings are polished during the production process, a smooth surface and no big noise is generated during the transportation. This entire ball transfer rolls smoothly and quietly through the drving of ball bearings. 5. WIDE APPLICATION: Ball roller bearings mainly help people move goods, not only at home such as sofas, showcases, carts, shelves, scooters, cabinets and kitchen appliances, but also in industries such as transmission systems, power systems, processing systems, packaging machines and Auxiliary machines.