Acorn International SB-MW15Z250 Self-Tapping Screw, #9 Thread, High-Low, Twin Lead

#9-15 metal to wood screws are sealing self-piercing tapping screws made from heat treated C1022 steel, case hardened for roofing and siding applications. A 5/16” across Zinc Alloy head with integrated EPDM seal washer offers easy driving and conforms to the metal surface for a secure, long-lasting optimum seal. The twin lead type 17 point and hi-lo threads offer faster drive time and greater resistance to pullout. All screws are 1,000 hour salt spray test dacro coated. All Acorn International screws are packed 250 pieces in a heavy duty tear-off resealable bag, UPC coded and retail ready. All bag and carton labels are trilingual. Cartons are heavy duty cardboard of uniform size.Self-tapping type 17 point with high-low threads, 5/16 in zinc alloy head, 1000 hrs salt spray coating, integrated rubber washer.