Used for attaching cills to the base of door or window frames. The self-drilling point permits the screw to drill through both reinforced and unreinforced frames. Thread Dia. mm: 4.2 Length mm: 65 Head Type: Bugle Recess Type: Phillips Thread Type: Self-Tapping Point Type: Self-Drilling Finish: Zinc Material: Carbon SteelSize 4.2 x 65 - 200 Pieces Timco Cill Screws - Bugle - PH - Self-Tapping Thread - Self-Drilling Point in Silver