Features: Material: Aluminum Alloy, Stainless Steel. Special Bowden Tube Fitting: PC4-M6; suitable for tubes with an inner diameter of 2 mm and an outer diameter of 4 mm. Brass gear: 40 teeth, inner diameter of 5 mm, outer diameter of 11 mm, height of 11mm. Groove bearing: 624U, groove diameter: 11mm, outer diameter: 13mm. Stability and durability: DIY kit, assemble yourself . Our kit includes all the necessary screws and parts to directly replace the old extruder. Suitable for 3D printer Bowden MK8 extruder holder 1.75mm long. Advantages of metal extruder: better pressure can be exerted through the printer nozzle to improve printer performance. Our extruder kit has an adjustable bolt so you can adjust the pressure of the extruder gear if needed. Easy to install: just remove the original Creality extruder, screw the new "metal extruder" and print. Upgraded 3D printer extruder block - Made of aluminum alloy, full metal, high quality and durable, able to improve the performance of the original printer. Wide compatibility: This aluminum actuator is a good replacement for the original acrylic parts for Creality CR-10, CR-10 S4, CR-10 S5 series, 3D printer. CR-10 Mini, CR-10s, CR-10 Plus.