Developed specifically for use with composite or synthetic decking materials and some medium density hardwoods. All work can be done quickly from above using basic tools (hammers screw gun).. Coverage based on 5.5in. decking with 16in. on center joists. #8 x 2in. stainless steel screws included. • Stainless • COMPOSITE & MEDIUM DENSITY HARDWOODS • Black Oxide Coating Coverage sq.ft.=50