Alright lads. Just a quick question. Ive got to nail or screw a bit of 9.5mm plasterboard on some timber at my mates house and then skim over it. Not a big job gladly. At college we just used normal nails to save on cost. Was told textbook to use galvanised or zink. Went in Wikes today and the drywall screws are black phosphated bugle head. Is this the same thing. Just want to make sure i get no rust coming through my skim.