Proxxon industrial tools are truly high quality, manufactured to standards that exceed those required by DIN and ISO. As proof of the quality, Proxxon have a 25 year guarantee against faulty material and workmanship. Made from the finest 31CrV3 chrome vanadium steel, all the pieces feature double nickel and single chrome plating giving the highest level of surface protection. The screwdriver bits are chrome-silicon-manganese-molybdenum alloyed special steel. The set comes in a sturdy steel powder coated case with carrying handle.