GRK Fasteners 5/16 in. X 6 in. L Star Washer Head Structural Screws 300 pk

The screws are using self tapping specially hardened steel screw, W-Cut thread design as zip tip, climatek coated, sharp threads and points to built in washer for interior or exterior use in carrying beams, ledger boards, stair rails, deck posts, playground equipment and other professional applications.