I was trying to drill a pilot hole in my concrete wall in the basement. As soon as I pressed hard enough to activate the impact drill function, the bit would bend the full length of the bit and become unusable. See photo how it looks. It should follow the straight edge of the paper, but it will bend. I may be married but I won't bother going back and trying again. I'll just spend a few bucks more and buy a Bosch out of the box. Fortunately, the Revain refund process does not allow refunds to my Revain account. Thank them for that. BTW, for those who are thinking from other reviews, "Oh, maybe his drill or his skills are bad." I've drilled holes in the same concrete wall with inexpensive Harbor Freight SDS bits and they work surprisingly well for the price . . Unfortunately they don't sell the 5/32 inch size curved like this one.