Scrw Dck Hdwd Ss Fh 10X2-1/2 Highly recommended for seaside applications and maximum corrosion resistance. Unique 4-corner thread-form with raised ridge technology greatly reduces driving torque. 6 lobe drive virtually eliminates driver bit cam-out. Self-countersinking nibs under hea d insure flush installation. Penetrate hardest wood products with ease; often without pre-drilling. Threaded approximately 2/3 up shank to tightly draw deck board to joist. Made of solid 316 stainless steel for maximum corrosion resistance. Contractor's Packs will fasten 500 square feet of decking (6" boards on 16" centers). Deck Packs will fasten 100 square feet of decking (6" boards on 16" centers). NOTE: DO NOT OVER-DRIVE.