Reply To: Screw size for trestles

I stick with PZ2 heads, 4mm shank, single threads at various lengths (and a countersink bit). Don’t go for the fancy heads or self drilling threads, just drill pilot holes and countersink them.
I also have 3.5 and 3 mil diameters as well, but they are not used nearly as much.
Every driver set you might buy, and any drill driver / impactor will usually come with a pozi-drive 2 bit.