DRYWALL TAPPING SCREW, Used for interior decoration of decoration industry, fasten gypsum board and keel on the partition wall, and in the condition of no prefabricated hole, can be screwed into the keel quickly. It has the advantage of double thread, strong hardness, fast tapping speed. The quality of thread lines directly affects the speed of tapping. Black is wildly used in the market, namely black parkerising. More than 80% of the demand for drywall tapping screws is focused on the specification 3.5x25.Because basically use at plasterboard, and the thickness of plasterboard is the same.