1000 x SD Screw 38x4.2mm Countersunk Head with Point Wings

The screws feature a point that will self drill and thread without the need for pre-drilling. Depending on the gauge, thread pitch, thickness of material and application, these screws will drill through steel up to 4.0mm. The clever wings on these countersunk head screws, drills a clearance hole in timber. This prevents the timber from rising up as the screw penetrates the metal, and negates the need for pre-drilling. As the screw point drills through the metal base material, the wings break off, the thread is formed and the head clamps down to secure the timber.