These carbon steel self-drilling screws with a Climaseal coating are designed for heavy-duty steel-to-steel applications without the need to pre-drill. They have a 1/4"-28 thread size, and a length of eight inches. These screws feature a 3/8-inch hex washer head and a Teks 5 drill point. They have a drilling and tapping capacity range from 0.125 to 0.500 inches and a maximum material attachment of 7.15 inches. There are 250 self-drilling screws per box.