Features: Auto leveling nuts Kit for 3D printers. 1.High-quality plastic material, durable and sturdy. Making your leveling process much easier, which is really a great way to upgrade your 3D printer with a little prices. 2.Easy to install and remove, no tools required. High quality leveling knob kit can make the printer much more stable and makes hot bed becomes much steadiness when printing. 3.The torque of the hand twisted nut is large, making it easier to fine tune the hot bed. And our knobs are made of ABS material, make the leveling is safer and does not hurt the hand. Specifications: Material: plastic Screw Length: 34.8mm(M4) M4 Nuts Color: Black M4 Nuts Length:58mm(M4) Springs Color: Yellow or Silver Yellow Springs Length: 25mm Silver Springs Length:19mm For: 3D Printer Advantages: Fast leveling in the way of rotation Made of high quality material, stable, heat resistant and durable Perfect 3D Printer replacement kit Easy and simple installation Hand Twist Level Nut. These nuts are original replacement part for Ender 3/3 Pro/3 X, Ender 5/5 Plus/ 5 Pro, CR-10, CR-10 V2, CR-10 Max, CR 10, CR-10 Mini, CR-10S, CR 10S Pro,CR-10 Plus, CR-X, CR 20. The springs are around 25mm long, which is longer than ender 3 and ender 3 pro printer springs. You can use a tool to cut it to be shorter if you really like this product or adjust the hot bed to be higher to fit the springs. Package list: 4 Nut, 4 Screws, 4 Springs. Note: Please allow slightly errors due to manual measurement and different monitors.