I never knew that, bugger me, might explain a few [1000] stuffed screw heads over the years. Thought only Phillips & Posi Drive. I always use a new Koken tip in an 8mm T bar if a problem & nearly always sorts it. plus tap the screw head to reshape it first, then smack the phillips tip in. Still got a hammer driver [impact driver] on the wall but seen a lot of damage done by those by the unwary--like the little countersunk screws on the small honda engine oil slinger end cover. [don't get me started] They do have a place though [the impact wrench].