There are two carbon steel ball bearings inside the pulley, which help reduce wheel friction. The pulley rotates smoothly and operates quietly. Made of stainless steel, it is rust-resistant and corrosion-resistant, suitable for outdoor use. Compared to other pulleys, this model features a thicker support plate, providing increased strength and higher load capacity. The pulley is removable for easy installation. Each pulley can support up to 660 lb (300 kg). Specification Product Name: U Type Pulley Color: Silver Material: 304 Stainless Steel Installation Height: 54 mm (2.125 in) Wheel Diameter: 48 mm (1.889 in) Wheel Thickness: 22 mm (0.866 in) Groove Width: 16 mm (0.629 in) Groove Depth: 7 mm (0.27 in) Product Weight: 280 g (0.617 lb) Load Capacity: 300 kg (660 lb) Application Commonly used as a grooved wheel for rail systems. Package Contents 2 x U-Type Pulley Note: Other items not included. Lighting and monitor settings may cause slight color variations between the image and the actual item. Measurement tolerance: +/- 13 cm.