Features: Brand new and high quality This kit is suitable for the upgraded of line rail to replace the pulley movement of original machine, which enables faster printing and longer service life. All the upgraded spare parts are precisely machined by precisions lathes, the process is mature and stable, and it is precisely matching with original machine spare parts, and the installation is more convenient and simple. When the machine starts to wear out from original pulley wheels and bearings, there are a few things you can do to get some improvement and possibly less headaches. The five line rails of the whole machine are upgraded, and the stable double Zaxis upgraded scheme is not unfamiliar. The purpose is to enhancer the Zaxis stability without losing the height of the Zaxis. Yaxis double linear guides upgraded, better than the single-track version and the wheel moving system. The profile of original machine needs to be replaced, the fixing screw hole position is added, and the milling grooves is added to adapt to original machine belt adjustment. The accessories are closely matching with original accessories, and the installation is simple. Specifications: Material:Metal Type:With Rail/Without Rail Package Includes: 1 Set 3D Printer Parts note: 1.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.