NEMA8 stepper, a worm gear set 1:40 with module 0.5, a drive gear (MK8 etc), 2 ball bearings ID 5 mm OD 10 mm for the gearbox, 1 ball bearing ID 3mm OD 10 mm for the pressure wheel, an idler arm spring, 5 mm shaft, 4 M2 screws for the stepper, a 4 mm bolt for the idler arm, some material for a heat brake between motor and plastic. A fan to cool the stepper motor, I used a crossflow fan that blows along the entire top of the printer.