Durable Material: To ensure practicality at work, the Groove Wheel Pulley is made of durable and sturdy 304 Stainless Steel, which is anti-rust, corrosion resistant, abrasion resistant, strong structure, and high hardness.Maximum Loading Capacity: 880lbs(400kg), wheel diameter: 48mm(1.9"). Groove width: 16mm(0.62"). Total size: 48x38x54mm/1.9"x1.5"x2.1" (L*W*H). Package contains 2 pcs U-type pulley block roller.Duplex Bearing Pulley Wheel: The track wheel pulley is designed with double bearings, and the surface has been polished to a very smooth finish. This helps the pulley to run more smoothly and quietly and prevents excessive friction from damaging the rope.Easy to Install: Drill a hole in the wall or the gate, and insert the expansion tube into the holes. Finally, fix the rigid caster with adopts self-locking screw.