Mk Morse Master Cobalt hole saws are perfect for the professional looking for high quality hole saws. These hole saws feature Bi-Metal M3 high speed steel cutting edge which is electron beam welded to an extremely strong steel backer which work very well together to provide faster and longer cutting action. The positive rake tooth design provides excellent chip clearance as the teeth of the hole saws cut through any machinable metal or any type of wood or plastic. The caps withstand a lot of abuse and punishment while at the same time are lighter and easier to use than most competitors. These MK Morse hole saw kits are perfect for all professionals and do it your selfers.