S.Drilling Screw - Star Head (1.5-inch)

Cavalry self-drilling screws, an inch and a half long, with a star-recess head. The head is the choice here: a star recess takes a driver bit rather than a nut setter, which suits somebody already driving other screws with a bit and not wanting to swap tools, and it sits flatter than a hex head where the next layer has to pass over it. The point drills its own hole through steel and cuts its own thread in one action, so nothing is pre-drilled. At an inch and a half it handles sheet with a thin spacer or underlay, deeper roof profiles, thicker purlins and shallow-cavity cladding. Drive at moderate speed and let the point cut before pressing; a star recess will cam out under real torque where a hex head will not.