The Allied Bolt Lag Screw (vendor part 1507, Millennium part 528389) is a 5/8 in x 5 in hex screw with a 15/16 in head, sized for heavy-duty pole line hardware attachment to telephone poles, packed 25 per pack. Grade 2 steel rated B70-B100 Rockwell hardness and hot-dip galvanized to ASTM A153 gives it the strength to anchor crossarm and guying hardware through years of outdoor loading. Its 5 in length reaches through thicker hardware stacks than Millennium's shorter lag screw options. Order with matching washers and square nuts for complete pole hardware assemblies.