Specification: Material: Iron, Bearing Steel Color: Titanium Color Size: 12 x 50 x 13mm/0.47 x 1.97 x 0.51 inch(ID x OD x Thickness) Groove: 10 x 7.5mm/0.39 x 0.29 inch(W x Depth) radian r=3 mm/0.12inch Bearing capacity: 512KG/1128.76 lbs Weight: 101g Features: 1. Inner diameter 12mm/0.47 inch, outer diameter 50mm/1.97 inch, thickness 13mm/0.51 inch, groove width 10mm/0.39 inch, groove depth 7.5mm/0.29 inch, radian r=3 mm/0.12inch, bearing capacity: 512KG/1128.76 lbs. 2. Grooved bearing pulleys are suitable for wire rope pulleys, transmission equipment, industrial pulleys, mobile garage doors, transmission machinery, etc., furniture hardware accessories, mobile doors, glass sliding doors, 3D printers. 3. Made of iron and bearing steel, strong and durable, it can be used in any environmental weathers for a long time. 4. The edges are smooth and won't scratch your hands, and the built-in bearings make it very quiet to use. 5. Please note the groove depth: 7.5mm (0.29inch), so the maximum rope thickness applicable is about 2/7inch. Package list: 1 x U Shape Pulley