If you had a cheap grain you won't believe the difference. That's the difference between a professional tool and a home use model. The photo shows how far you can unscrew the top cover to change the thickness of the dent. In the lower left corner you can see a piece of aluminum, I checked the depth of the punched dent. If you use it on aluminum you should unscrew the top as you see in the photo. A much smaller, much more precise and easier dent for your first drill. The accuracy of your work will increase dramatically! It's expensive but worth it.