PTA Drywall screws have very sharp pointy tip so it can pierce the drywall material easily. The threads are spaced moderately wide, since drywall may crumble easily. The bugle head of the screw keeps the drywall attached to the section and the entire screw lies flush with the surface of the drywall, creating a smooth and even finish. The Bugle head also aid to prevent the drywall screw from breaking the paper surface, a common problem with nails.
PTA drywall screw can be readily identified by its jet black finish. This jet black color comes from a phosphate mineral coating that is applied to these screws. This coating helps to minimize rusting and corrosion as the screws are often exposed to wet joint compound or paint.