I lost the wrench that came with my grinder. Anyone who has ever had to improvise to remove a lock nut knows what a real headache it can be. I tried to pick up an old wrench but my grinder is old and couldn't find it. I chose this one because it is adjustable (see photo). I was so happy with this B!ue Stars key that I'm actually reviewing it (I was a reviewer for nine years but quit. Accused of trolling or advertising). the product.ugh.who needs it.) Anyway, the convenient button is a nice bonus; the adjustment knob is solid and he tightened the nut with no problems BUT more importantly he removed the lock nut (which is always tight when used) smooth as a band. So well done! A good tool.