There are two carbon steel ball beas inside the pulley, which can reduce the friction of the wheel. The pulley turns more flexibly and has no noise.< />Stainless steel manufactu, rust - proof, corrosion - resistant, outdoor use can also prevent pulley corrosion.< />Compared with other pulleys, pulley wheel support plate is thicker, the wheels are stronger and the bea is stronger.< />Pulleys are removable for easy installation. A single small pulley can carry 660lb/300kg< />Specification< />Product Name: U Type Pulley< />Color: < />Material: 304 stainless steel< />Installation height: 54mm(2.125in)< />Wheel diameter: 48mm(1.889in)< />Wheel thickness: 22mm(0.866in)< />Groove width: 16 mm(0.629in)< />Groove depth: 7 mm(0.27in)< />Product weight: 280g(0.617lb)< />Load: 300 kg (660 Ib)< />Application< />Generally used as a rail wheel Grooved Wheel< />Package Conten:< />1pcs * U-Type Pulley