Tru-Cut Manufacturing's SDS-Plus drill bits are made in the U.S.A. Starting with the highest quality domestic alloy steel; next, they can obtain carbide tips for their bits to be higher quality than the competition. The SDSSET6 kit contains bits that have carbide tips that are more than copper brazed and treated without the use of flux in their state of the art Vacuum Furnace that produces stronger braces without voids. Finally, Tru-Cut Manufacturing shot peens the outer surface to skin harden the drill bits. With the extra effort and engineering that Tru-Cut puts into their drill bits, our customers can expect more holes at a competitive price than any foreign competitor.