10-16X1 1/4 Combo (Slotted/Phil) Ind Hex washer 1/4" Across Flats Full Thread Self Piercing Screw Zinc (Pack Qty 3,000) BC-1020PCW

May be used in thin metal (less than .050 thick). Eliminates need for pre-drilled or pre-punched holes. Undercut area beneath the head allows greater length of thread engagement. Twin lead threads help to reduce driving torque AISI 1018 - 1022 or equivalent steel Screws shall be quenched in liquid and then tempered by reheating to 650°F minimum