This is a 7-Piece The Edge Forstner bit set from Mibro. Sizes are 1/4-Inch through 1-Inch in 1/8-Inch increments. The patented serrated edge easily removes chips and dissipates heat, increasing cutting speed. The razor sharp cutting edge means exceptionally accurate, smooth flat bottomed holes. The tough titanium nitride coating over the high speed steel bit guarantees performance in hardwoods and abrasive composite materials. Forstner bits have 2 cutting edges that are designed to cut perfectly clean holes and to leave a flat bottomed hole. They will cut over-lapping holes easily regardless of grain direction. These bits should be used at a slow speed. Forstner bits require more pressure than other drill bits and are generally used in drill press or lathes.Faster - Patented, serrated edge easily removes chips and dissipates heat, increasing cutting speedCleaner - the serrated edge and razor sharp cutting edge means exceptionally accurate, smooth, flat bottomed holesTougher - high speed steel with a titanium nitride coating guarantees performance in hardwoods and abrasive composite materialsConvenient wood storage case