Features 5 PCS SET: The kit contains 2 pcs extrusion gears, 1 pc shaft, 2 pcs needle bearings, compatible with multiple 3D printer models. SUPER HIGH HARDNESS: Forged from hardened steel, the overall hardness reaches HRC60+, the parts are more sturdy and stable. RNC NANO COATING: The surface is RNC based nano coating, with ultra high hardness HV330, more wear resistance. PRECISE SIZE: The dimension accuracy of the inner hole is 0.02mm, the gears could be closely matched with the shaft and has high concentricity. WIDE COMPATIBILITY: This 3D printer dual drive gears kit is compatible with multiple models, easy to replace and install. Specification: Item Type: 3D Printer Extruder Gear Material: Hardened Steel Gear Hole Diameter: Approx. 5mm/0.2in Package List:2 x Gears 1 x Shaft2 x Needle Bearings Note:Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering. Package List 2 x Gears 1 x Shaft 2 x Needle Bearings