Thin enough to sit nearly flush in masonry and concrete without countersinking. These screws also have a wide head that spreads pressure evenly to help prevent thin materials from deforming. Also known as Heavy Duty Tapcons, they have hardened steel threads that cut deep into concrete for a strong hold. Create a pilot hole using a hammer drill or rotary hammer and a compatible bit. Pull-out strength and shear strength values are 25% of the ultimate values.

Secure framing to metal in tight-clearance spots where corrosion resistance is required. Also known as panel clip screws, these screws have a slim pancake head that creates a nearly flush finish. The head's flat underside makes more contact than other rounded-head screws for a better hold on thin materials, such as sheet metal and plywood. Drill and fasten screws in one step using a Phillips driver.

Length is measured from under the head.