Red Metal MK8 Extruder Aluminum Alloy Block Bowden Extruder 1.75mm Filament 3D Printer Extruders For Ender 3 3pro Ender-5 CR-10 Description: This modified MK8 Extruder has a filament guide tube, all screws, spare drive gear, and upgraded Bowden tube fitting, for CR-10 3D Printer. Our design gives complete support of flexibles from the intake and output ends. Weve reduced the price and complexity of printing flexibles. It will also allow to print faster with sustained quality and no risk for grinding the filament. Upgraded Aluminum Extruder Drive Feed kit, which can replace the acrylic parts. It is more stable and durable for all 1.75mm filament. Upgrade Aluminum Extruder Drive Feed Frame For Creality 3D Printer.