High-quality and durable materials. The bearing surface of the transmission unit is made of galvanized iron, which is scratch-resistant, corrosion-resistant, rust-resistant, stable, not easily damaged, and offers a long service life. The product has good load-bearing capacity with a maximum load capacity of 20 kg. The roller features a 1.6 cm hardened steel ball that rotates on a 0.3 cm internal bearing for smooth motion. 360-degree silent rolling. The roller unit ball bearing transmission is polished during production, resulting in a smooth surface. The universal 360-degree transmission bearing is flexible, fast, and stable, with low noise during operation. Equipped with screws for easy installation. The product includes 16 screws. The drive bearing has two screw holes. Simply use screws to attach the nylon ball conveyor to the items to be transported. Suitable for various applications. Ideal for use with sofas, display cases, carts, shelves, scooters, cabinets, and kitchen equipment. Also suitable for system transmission, power systems, processing systems, and packaging applications. Two-hole nylon bearings designed for use in transmission systems, power systems, processing systems, and processing machinery. Made from premium materials. The ball transfer roller is constructed from high-quality carbon steel, ensuring strength and durability, with excellent wear resistance and long-lasting performance. 360-degree swivel casters provide high-speed, stable operation, ideal for rotating and changing the direction of conveyor belts. Good load-bearing capacity. Each caster with bearing can support up to 20 kg, helping reduce work intensity and operator fatigue. Low noise operation. The smooth surface of the ball bearing transfer wheel ensures quiet performance during transportation. Includes two screw mounting holes. Package includes 16 screws for easy installation. Wide range of uses. Commonly used in conveyor belt pipeline installations, household appliances, transmission systems, processing systems, wooden boxes, adjustable furniture, workbenches, and more. Specifications: Material: Galvanized iron plate + nylon Color: As shown in image Screws: 4 x 16 mm Weight: 250 g Package includes: 6 two-hole nylon bearings Note: Due to manual measurement, actual dimensions may vary by 0–2.5 cm.