You're building or re-siding a pole barn, a machine shed, or an ag building with pressure-treated lumber — and the nails you're using keep backing out, or the siding is loosening up after a season. Pole barn siding needs ring shank nails. This 20d hot-dipped galvanized ring shank nail is built for exactly that. 20d nail means 20-penny — approximately 6 inches long and heavy enough to penetrate through modern pressure-treated lumber. Ring shank profile grips the fiber laterally in addition to axially, giving the nail resistance to withdrawal that smooth shank nails simply don't have. Hot-dipped galvanized coating provides corrosion resistance for the treated lumber environment — the coating weight matters here, and HDG is the right call for treated wood contact. Sold by the pound. Standard Stocked at Crofton Lumber and Akron Lumber.