Drywall Metal Stud Plasterboard Screws - Fine Thread - 3.5 x 42mm - 1000pcsUsed to secure plasterboard to wall ceiling track systems with a max. of 0. 6mm thickness. Phillips No. 2 recess for a positive drive Bugle head to reduce likelihood of damaging the board surface 25 super sharp point for ease of penetration 60 twin thread offers excellent pull out values and insertion speed Fire Classification A1 Pack Quantity: 1000 Pieces