Item Type: Extruder Drive Feed Kit Material: Aluminum alloy, brass, stainless steel Nozzle Size: Approx. 0.4mm / 0.02in Filament: Approx. 1.75mm / 0.07in Package List 1 x For CR10 Extrusion Head 6 x Screw 1 x Spring 7 x For CR10 Pro Extruder Splicing Accessories 1VERY GOOD DRIVE: Direct drive extruder, possess high extrusion force, enhanced feeding strength, ensure smooth feeding, better pressure to push the filament into the printer, not easy to lose steps 2APPLICABLE MODEL: Dual gear mk8 extruder, perfect replacement for 1.75mm filament of 3D printer for CR 10, for CR 10S, for CR 10S Pro, for Ender 3(initial version), for Ender 3 v2, for Ender 3 pro, for Ender 5, for Tornado etc. 3ADJUSTABLE TENSION: Compared with ordinary plastic drive, this aluminum alloy double gear extruder is stable and durable. The tension of the compression spring can be adjusted by tightening the screw, which greatly improves the printing accuracy and paper feeding problems 4FIRM AND SLIP FREE: A firm grip on the filament between two threaded wheels that lock together with a dual gear swivel design instantly delivers improved print quality and reduced filament slippage. No more skip steps after high speed squeezing or retracting 5WIDE RANGE OF APPLICATIONS: Extruder kits are widely used in assembly hot end kits for Ender 3, for CR10, for CR 10 Pro, for CR 10S