Features: Brand new and high quality Upgraded the Single Z Axes structure to a double Z Axes structure, avoiding a backlogs of filaments thoroughly, which improves the stability of 3D printing. Compared with original structure, the double Z Axes kit reduces the layer ripple caused by Z Axes vibration, increasing the printing performances of the 3D printer. Both ends of X Axes are raised and lowered synchronously, which reduces the difficulty and frequency of bed leveling obviously. Compared with the Closed Timing Belt, this 3D printer parts set still retains the design of the stepper motor to ensure screw rod smooth operation. No need to modify or welding the machine, no need to replace the motherboards, this 3D printer accessories kit comes with instructions and could be assembled quickly. Specifications: Material:Metal Type:B1/B1 SEPlus/Hurakan Package Includes: 1 Set Double Z Axes Upgraded 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.