Feature:1. This linear rail guide is made from quality bearing steel material, which has high hardness and durability.2. With professional and premium guide rail and stopper, this linear rail guide is sturdy and durable.3. The linear rail guide ensures high accuracy and stable performance, small and lightweight, suitable for most automation equipment.4. Equipped with two rubber stoppers on each side of the linear rail, it can prevent the carriage block from falling out5. This linear rail guide is suitable for Ender3/Corexy/Delta Kossel 3D printer upgrade and CNC machine.Specification:Item Type: Linear Rail GuideMaterial: Bearing SteelModel: MGN12CRail Height: Approx. 6.5mm / 0.25inRail Width: Approx. 12mm / 0.47inLeading Thread: M3Guide Hole Spacing: Approx. 20mm / 0.78inLength (optional): Approx. 100mm / 3.93in, 150mm / 5.9in, 200mm / 7.87in, 250mm / 9.84in, 300mm / 11.81in, 350mm / 13.77in, 400mm / 15.74in, 450mm / 17.71in, 500mm / 19.68in.Package List:1 xLinear Rail Guide