2.5 in. long thread rolling (thread forming) screw

The Hex Washer Head has a flat washer that extends beyond the sides, providing it with a greater bearing surface than a normal hex head fastener. The washer and the Hex Head are bonded together as one piece; this offers greater protection to the mating surface than a standard hex head. The increased bearing area decreases the likeliness of crushing mating surfaces. Trilobe, or Thread Rolling, screws have a blunt tapered point that requires a pre-drilled or punched hole; eliminates chips and permits replacement with standard screw. Zinc plating, retards the corrosion rate in a normal atmosphere.