Two Bearings: With 2 bearings, the roller can rotate smoothly and will never jam, which can prevent the rope from breaking due to excessive friction. Silent Pulley Wheel: All parts are installed firmly, and the gaskets are placed in the gaps, do not collide with each other and make metallic noise. 500 kg Load: The pulley is made of 304 stainless steel, and all parts are thick. Self-locking Nut: φ18 mm. Compared with ordinary nuts, it can resist loosening and vibration. 360° Swivel Ring: The pulley block can be rotated 360 degrees to prevent the rope from tangling.