PZ are useless as a standard because it's not significantly different enough from others, and you can't tell which PZ you need.
Torx and hex is brilliant because you can easily say which shape of bit you need, and you'll instantly know if you pick the wrong one.
Luckily Torx seems to have finally won and screws that require any kind of moment (construction/decking/fasteners/) now seem to use them in stores, while only the kind of scre you'd hang up a picture frame with is PH/PZ.
I have never seen a square (Robertson?) screw in the wild, I assume that's regional.
Luckily Torx seems to have finally won and screws that require any kind of moment (construction/decking/fasteners/) now seem to use them in stores, while only the kind of scre you'd hang up a picture frame with is PH/PZ.
I have never seen a square (Robertson?) screw in the wild, I assume that's regional.