At first glance Colt "Twinland" bits may appear to be a 4 fluted, however, a closer look shows that the bits have a slight relief milled in the land (flat area between the flutes) to create 4 lands rather than 2. The extra lands improve guidance when drilling by hand, and help seal the flutes to prevent chip squeezing and burning. The flutes are milled at a 25 degree angle, which vastly improves chip ejection and helps reduce friction and burning. The flutes are roll forged and the cutting tips have been diamond ground to stay sharper and last longer . Ideal for boring holes in softwoods, hardwoods, exotic woods, veneers, and laminated wood. Bits under 3/4" have 3/8" or smaller shanks. Bits over 3/4" have 1/2" shanks. Made from alloy steel. Germany.