Brand new and high quality Feature: This is a great addition to your Ender 3, Ender 3 Pro, not fit for CR10 series. It gives you that for extra height when you need it : Adds 5.9 inches to your z height of your Ender 3 Printer. Package includes: 2Pcs 550mm/ 21.6 inch 2040 Aluminum Extrusions+1Pcs T8 Lead Screw Set+ 3Pcs Longer Motor/ Limit Switch Connect Cables+Marlin firmware Setting tools Easy to install: comes with everything you need in the box. Install instruction Please reference the video on the pictures. You will need to use a custom marlin firmware to use the full potential of this product, the kit has comes with the marlin update tools. After installing, extender height from stock 220mm/ 8.7inch up to 400mm/ 15.7inch, printing area up to:235*235*400mm/9.2*9.2*15.7 inch, Kindly Tips: Make sure to make a drawing or take a picture of the original setup before you disassemble in for case you need to refer back to it. Just take off the power supply, the top rail, the Z stepper motor, if you still use it, the Z End Stop bracket and the rail holding the hotend and extruder. Change the setting in your firmware from 250 to 400. Specifications: Material: Metal Length: approx.55cm/21.65in Color: As pictures shown Quantity: 1 Set Note: No retail package. Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package Includes: 1 Set x Z-Axis Upgrade Kit (other accessories demo in the picture is not included)