A unique thread design and quality controlled manufacture spell the Zip-In difference. Zip-In's sophisticated heat treat process allows the screw to taper to a fine, sharp point without sacrificing critical point strength. A single starting thread is formed down to the very tip of the point and is the source of Zip-In's penetrating power. A second thread above the point engages after initial penetration and drills in the screw double fast. Zip-In screws are faster driving, with a greater capacity for fastening heavier gauges of sheet metal than any other self-piercing type.
Undercut - indented hex washer slotted head|Bright zinc plated|Burr free|Full 1/4 in (No 8) head will not strip out of hex driver opening|One 1/4 in hex driver accommodates all sizes|Undercut - always seats flush|Some screws sizes available in pails|Trademarked and patented head markings indicate one and only genuine zip-ins|Combination lead double thread design single starting thread machined down to very tip of screw point, Instantly penetrates and engages in heavy gauge sheet metal and layered light gauge|Consistent hard point quality controlled heat treat|Sharp tapered point will not mushroom or break|No walking
Malco Zip-In Sheet Metal Screw, Self-Piercing, Measurement System: Imperial, #8 Thread, Hex Washer Head, Slotted Drive, Zinc Plated, 1/4 in Head, Double Thread, 2 in Thread Length, White