Product Description Simpson strong-tie deck screw, no 7 screw, 3 in length, trim head, T15 drive, 6-lobe torx drive, sharp point, 0.23 in head, 316 stainless steel. Hardwood decking screws easily penetrate the hardest wood products. Unique 4-corner thread form with raised-ridge technology reduces driving torque. From the Manufacturer Simpson 316 Stainless Steel Hardwood Decking Screws penetrate the hardest wood products with ease. Unique 4-corner thread form with raised-ridge technology greatly reduces driving torque. Threads are approximately 2/3 up the shank to tightly draw the decking to the joist. 316 Stainless Steel for seaside applications and superior corrosion resistance.