A single starting thread (A) is machined down to the very tip of the point and is the source of Zips penetrating power. A second thread (B) above the point engages after initial penetration and moves the screw in double fast. Zip screws are faster driving, with a greater capacity for fastening heavier gauges of sheet metal than any other self-drilling type.
Quantity 1000 – 5000 and available in larger quantities.
