@@PhanTuongNhat Because the handle has a short diameter, the force required to wind the finger is added to the scale. It is difficult to explain, but as far as I've seen, if the handle is thin, it's definitely high. If you are concerned, I recommend changing the handle of the fake GM150 to a thinner type. Also, the AK-150 uses bearings for rigid duralumin and sliding parts, so it conveys all the force👍