5/16"-18 x 2 T-40 Flat Head Self Tapping Trailer Deck Screws, 100 Pack — Open-Box, 13% Off

TYPE F SELF-TAPPING POINT - cuts machine threads directly into steel crossmembers up to 1/4" thick; drill a pilot hole, drive with an impact, no nut and no pre-tapping

FLUSH COUNTERSUNK FLAT HEAD - nibs under the head cut a clean countersink in hardwood and softwood decking, so nothing catches a boot, a strap or a skid

STAR DRIVE, NO CAM-OUT - deep six-lobe recess takes full impact-driver torque without stripping; far more re-drives than any Phillips deck screw survives

REMOVABLE, SERVICEABLE JOINT - machine threads in the steel survive board replacement; back the screw out, drop a new board, drive the same screw home

SPECS (5/16"-18 x 2") - T-40 star drive, 17/64" pilot in steel; suits 1-1/2" boards over steel frames; steel Type F thread cutting screws, made for trailer deck and floorboard replacement

Self-tapping trailer deck screws, 5/16"-18 thread x 2" long, flat countersunk head, T-40 star drive. The Type F machine-screw point cuts its own threads into drilled steel crossmembers up to 1/4" thick - drill a 17/64" pilot in the steel, drive through the deck board with an impact driver, and the screw pulls the board tight to the frame with a machine-thread connection. This length suits 1-1/2" boards. Unlike lag screws or drill-point screws, the tapped threads survive board replacement: remove the screw, replace the board, re-drive. The countersunk head with cutting nibs seats flush in hardwood and softwood decking. Use on utility trailers, equipment and flatbed trailers, dump beds, truck bodies and any wood-over-steel floor. Sold in contractor quantities; star drive bits fit standard T-40 bits.