Very good extruder. I replaced mine from my Anycubic Mega S. An assembly instruction would be nice, but I took it as a puzzle and it was done in 5 minutes. There are extra screws attached, you will have some remaining do not panic! Since the delivered gear for the motor has no centric hole for fixation, I had to turn it upside-down to mount it propperly on the NEMA stepper. Now the screwhole runs over the surface of the big gear, but I think it is ok. For mounting it an an Anicubiy, you will not need the attached holder (L-Shaped bracked with round hole), you may use the existing one, turning it also upside-down from the original position. Great Item, gret price!
just as described as as far as I can tell the quality is just as good (if not better) than the original. I'm super impressed with the quality.