NOTE - The length of springs are about 25mm, which is slightly longer than the ender 3 series printers(Including ender 3/ender 3 pro/ender 3 v2). The springs need to cut them shorter than the original ones in order to adapt them to the printer or adjust the hot bed to be higher to fit the springs. Suitable for - Upgraded aluminum hand twist level nut are original upgraded replacement part for Ender 3/3 Pro/3 V2/3 Max, Ender 5/5 Plus/ 5 Pro, CR-10, CR-10 V2, CR-10 V3,CR-10 Max, CR 10, CR-10 Mini, CR-10S, CR 10S Pro,CR 10S Pro V2, CR-10 Plus, CR-X, CR 20. Metal Material - Metal material is stronger, it will twist more tightly than plastic nuts. Easy to use - The torque of these nuts is large, making it easier to fine tune the hot bed. Quality - Made by high quality aluminum, last much longer your stock plastic nuts.