These roofing nails, manufactured in B.C. by Tree Island, have an enlarged 7/16" flat head suitable for preparing roofing, asphalt, shingles, insulation board and felts. They have a hot galvanized finish, diamond point and a round, smooth shank. Hot galvanization provides dual protection by serving as both a barrier coating and a sacrificial coating. Tree Island hot-dipped galvanized nails exceed ASTM A153 Class D. Hot-dip galvanized nails are recommended for use where high corrosion resistance is required such as outdoor exposure and for use with pressure-treated wood.