1/4-10X3/4 Slotted Ind Hex Washer 3/8" Across The Flats Full Thread Self Piercing Screw Zinc Needle Pt (Pack Qty 2,000) BC-1412PSW by Shorpioen

AISI 1018 - 1022 or equivalent steel: 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. Screws shall be quenched in liquid and then tempered by reheating to 650F minimum | 410 Stainless: Offers similar advantages as the steel screw of the same design but with better corrosion resistance. It is important to remember that the hardness of the material to be fastened should be a minimum of 10-20 Rockwell hardness points LESS th | 410 stainless screws shall be hardened and tempered by heating to 1800-1900F sufficient for austenitization, held for at least 1/2 hour and rapid air or oil-quenched then reheating to 500-600F for at least 1 hour and air cooled to provide the specifie