Complete sign bolt kit 5/16-18x1" stainless steel hex head bolts, nuts, flat washer & lock washers. Designed for installation via spanner, the hexagonal heads are a more favorable size and shape for heavy-duty applications. Fully threaded with industry-standard coarse threads, these carriage bolts are suitable for situations where the fastener shaft is completely inserted into threaded hole and can secure two threaded sections. Chemical resistant, made of 18-8 stainless steel with zinc plating. 95TSS has everything else you need, from galvanized steel sign posts to quality .08 aluminum traffic signs.