Features:With precise hole location, easy to install.Made of high reliable quality and durable material.Advanced manufacturing technology, high reliability and high performance.Low upgrade cost, cost-effective(high cost performance, technical guidance, mature solutionA must have upgrade kit for your Ender 3 printers, let your printer more durable. Adjust the belt and also suitable for Ender 3 Pro Cr10. Specifications:Model Type : Dual Z-axis Belt StretchColor: BlackWeight:700g Material: MetalSize:Pls See the Picturesfor: Ender-3 / Cr10 (Optional)Package Size: approx 55.5x14x5cm/21.85x5.5x1.97in for CR10 approx 41x16x8cm/16.14x6.3x3.15in for Ender-3 Note:Due to the problems of lighting effects and shooting angles, there will be certain tolerances in the product, please understand.Please allow 0-1cm error due to the manual measurment. Package includes:1 Set Dual Z Axis Belt Stretch