Roofing and siding nail, electro-galvanized, primarily used for applying roofing asphalt shingles, insulation board and felt-to-wood substrates. Large head and heavier shank gauge provide greater holding power. Electrogalvanized nail also appropriate for use with vinyl siding. PrimeSource Building Products, Inc. is the largest purveyor of fasteners in the world and one of the largest distributors of building materials in the United States.