ITEM NAME:MK8 Extruder Upgrade Kit Spring Stepper Dampers for CR10 Ender3 CR-10S img *{margin:0;padding:0;.1 x Aluminium Extruder Assembly. Two high quality NEMA 17 stepper dampers are included one for mounting on the X stepper motor and another for the Y stepper motor. Installing these gives a drastic noise level reduction from your 3D printer.