18" Class 300 Flange Bolt Kit ASTM A307 Grade A Zinc$0.00PriceOut of StockComplete Class 300 flange bolt kit for 18" ASME B16.5 flanges. Contents: (24) 1-1/4"-7 × 7-3/4" ASTM A307 Grade A Zinc-Plated Hex Machine Bolts and (24) 1-1/4"-7 Zinc Finish Hex Nuts.