Ours came defective,the bit doesn’t fit the adapter, the paint is scratched up on the bottom and it’s missing several of the diamond parts on the bit. They were not in the package so it came that way.that would affect the way it worked so is a big problem. As you can see from my pictures the diamonds are missing, the scratches on the bottom, are just cosmetic I would think, although it could rust. The picture showing that it didn’t screw in all the way shows the problem with the bit, the adapterSee full review