Where most forstners have round shanks that can easily slip in drill chucks and gall, Sommerfeld's forstners have rugged, hexagonal shanks, giving you increased gripping power with zero fear of slippage. A special cutting flute design, sharp center points and hexagonal shanks help these bits cut cleanly, on target and without slippage. Designed to produce holes with super-smooth sides and perfectly flat bottoms, results are best when these bits are used in a drill press at a slow speed. Since chip ejection on forstners is notoriously inefficient, it's also best to withdraw the bit from the hole freqeuntly to clear the chips.

Set includes: 16 bits, with diameters ranging from 1/4" to 2-1/8", in 1/8" increments. (all with 3/8" shanks)