Features: Brand new and high quality Wear resistant, strong hardness, quiet and wear-resistant, smooth rolling, high hardness, strong load-bearing, precisions machining, good coordination, quiet design. High hardness, sturdy and durable, high-strength medium carbon steel precisions machining, tight forging process, surfaces treatments smooth without burrs, uniform stress, beautiful and smooth design. High quality bearing steel rolling bearing, smooth rolling with low noise, embedded bearing SUS420 stainless steel bearing, low resistance, smooth operation, high printing accuracy, and lower noise. Carrying a weight of 1256 kilograms. Craftsmanship, quality, precisions craftsmanship, coaxiality, flatness, precisions coordination, good hardness, high load-bearing capacity, and the use of new production processes and equipment processing ensure the flatness of each component and the concentricity of bearings, ensuring the smoothness of the printer operation and the smoothness of its jumping after multiple rounds of assembly. Multiple scenarios and uses, including household sliding doors, wardrobes, large iron doors, curtains, automation equipment pulley component, factory track pulleys. Specifications: Material: Aluminum alloy Size: 80x34x40mm Machining type: cutting Size: diameter 30mm, length 200mm Tolerance: ± 0.01mm Processing material: iron, S45C Surfaces roughness: RA0.8 Processing methods: cutting, welding, rivetings Package Includes: 1PC 4 Wheel Trolley Assembly note: No retail package. Please allow 0-1cm error due to manual measurement. make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!