Designed For Pocket-Hole Systems, Kreg Pocket-Hole ScrewsIncrease The Strength Of A Pocket-Hole Joint. Cut-Thread Pattern PreventsSplitting. Coarse Thread Is For Any Combination Of Softwoods, Plywood, AndComposites, And Fine Is For Hardwoods. Assortment Includes 150 Each Of 6 X 1″Fine, 7 X 1″ Coarse, 7 X 1-1/4″ Fine, And 8 X 1-1/4″ Coarse. It AlsoIncludes 75 Of The Blue-Kote Weather-Resistant 8 X 2-1/2″ Coarse Screws. Fromthe Manufacturer This kit contains five of our most popular self-tapping screwsizes for Pocket-Screw Joinery, in a durable easy-to-carry case. All Kregscrews feature a deep 2 square drive, a needle-point self tapping tip, and acase hardened design built for strength.