Used to secure plasterboard to timber stud work. The collated strips are specifically designed to be compatible with all leading power tool brands. NOTE: Partially threaded. The collated strips are specifically designed to be compatible with all leading power tool brands Fire Classification: A1" Thread Dia. mm: 4.2 Length mm: 75 Thread Length mm: 50 Head Type: Bugle Recess Type: Phillips Point Type: 25 Sharp Driver Bit Size: PH2 Finish: Black Phosphate Material: Carbon Steel Max Drilling Thickness mm: N/ASize 4.2 x 75 - 500 Pieces Timco Collated Drywall Timber Stud Plasterboard Screws - PH - Bugle - Coarse in Black