& OOTDTY Features: Mechanical metal process knob or other work with the appearance of rolling pattern for anti-slip. It is a diagonal pattern designed, perfect for a damaged pulley. Rigidity, wear resistance, damage resistance, long service life. Two rollers oblique direction: one is positive and the other is negative. Specification: Material: Steel Pitch: 1.0mm, 1.2mm, 1.8mm, 3.0mm Outer Diameter: 25mm/0.98 inch Bore Diameter: 8mm/0.31 inch Thickness: 8mm/0.31 inch Color: Grey Quantity: 2pcs/set Note: 1. Please allow 0-1cm error due to manual measurement. Pls make sure you do not mind before bidding.2. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package Included: 2 x Diagonal Knurled Wheels (Without Retail Package)