ROBERTS 13 Gauge Drive Screw Nails are made of brass to offer superior strength, durability, and resistance to corrosion. Their 1-1/4" with 3/16" Nail Heads are designed to provide a "flush" fit when used to anchor carpet bar and stair nosings. As the spiral shank is driven into the substrate, it forms a screw-shaped hole for better grip and hold, which prevents the nail from loosening and prevents damage to the substrate. Ideal for flooring installation, 1 lb. bag contains 50 pieces.