Big Timber STX Flat Head Star Drive Wood Screws in Marine Grade 316 Stainless Steel are ideal for all applications using hard or soft woods, engineered woods and ACQ treated lumber. Type 316 SS is ideal for demanding exterior work on any application that requires a highly rust and corrosion resistant fastener. STX Stainless Steel wood screws feature sharp, deep cutting threads and a knurled shank for easy driving and a strong grip into the material. A notched quick-starting Type 17 point prevents the screw from “walking’ during installation. The Flat head with the high torque 6-Point Star (Torx) Drive features Self-Countersinking Nibs to draw the screw head flush to the work surface.