Product Material: Galvanized Iron Color: Silver Ball Material: Nylon Ball Diameter: 16 mm (0.63 inch) / 25 mm (0.98 inch) 16 mm Unit Dimensions: 48 x 32 x 20 mm (L x W x H) 25 mm Unit Dimensions: 75 x 50 x 30 mm (L x W x H) Package Includes: - 4 x Ball Transfer Units - 8 x Mounting Screws - 1 x Screwdriver 1. Package Contents: 4 x Nylon Ball Transfer Units, 1 x Screwdriver, 8 x Mounting Screws, and 16 mm or 25 mm Diameter Round Ball Transfer Units. Designed for compact installation spaces with two screw-mounting holes. 2. High-Quality Materials: Main body constructed from galvanized carbon steel for scratch resistance, corrosion resistance, and rust resistance. Durable and long-lasting. 3. Smooth Operation: 360-degree rotation for effortless movement. Enables efficient handling of goods and time-saving operation. Maximum load capacity per unit: 15 kg. Suitable for a wide range of applications. 4. Quiet Performance: Precision-polished surfaces and ball bearing design ensure smooth, silent operation during use. 5. Wide Application: Ideal for furniture (sofas, cabinets, shelves, carts, kitchen appliances), industrial equipment (conveyors, packaging machines, processing systems), and other material handling needs.