●Material: The concrete screw is made of Q235 carbon steel, with high hardness, galvanized surface, and corrosion resistance. ●Application: Suitable for heavy loads such as solid concrete, stones, bricks, etc. ●Durable: Flange hexagonal washer head with anti rotation serrations, safe and secure. ●Size: 1/4 "x 2". ●Packaging: 10 concrete screws in total.