Product Material: galvanized iron Ball material: nylon Ball diameter: 16 mm / 0.5 Inch, 25 mm / 1 Inch 16 mm dimensions: 48 x 32 x 20 mm (L x W x H) 25 mm dimensions: 75 x 50 x 30 mm (L x W x H) Package includes: - 4 x roller transfer - 8 x screw - 1 x screwdriver 1. DELIVERY CONTENT: 4 x nylon furniture casters, 1 x screwdriver, 8 x screws, 16 / 25mm diameter round ball transfer. 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, and rust resistance. 3. COMFORTABLE AND PRACTICAL: 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, suitable for most objects. 4. NO NOISE: The transfer units of the roller ball bearings are polished during the production process, providing a smooth surface and generating no big noise during transportation. This entire ball transfer rolls smoothly and quietly through the driving of ball bearings. 5. WIDE APPLICATION: Ball roller bearings help move goods easily, suitable for home use such as sofas, showcases, carts, shelves, scooters, cabinets, and kitchen appliances, as well as industrial applications like transmission systems, power systems, processing systems, packaging machines, and auxiliary machines.