ASTM A325M Bolt High-strength Structural Bolting Assemblies Hex Bolt What does grade A325 mean? A325, which is ASTM A325 and an international standard for heavy hex bolts or structural bolts, from American Society for Testing and Materials, ASTM A325 bolts are used in high strength and high tension applications, and ASTM A325 bolt dimensions are metric sizes M12 to M36 and imperial sizes are 1/2'' to 1 1/2''. Fastenwell as a bolt factory and a325 bolt manufacturers, hex bolts, hex heavy bolts and heavy hex structural bolts are our main products in regular production in Asia, Middle East and America market. What grade steel is A325? A325 bolt grade are made of medium carbon steel, alloy steel or material B7 with high strength to used in construction applications like steel structure, space frame, building, bridge and highway projects. Structural bolts grade 8.8 and ASTM A325 galvanzied are our best sellers among customers like construction contractors and building material wholesalers. What is A325 material? A325 material are heavy hex structural bolts made of medium carbon steel, alloy steel and material B7 depending on customer's requirements, which usually working in structural steel connections and heavy construction projects while working with structural nuts A563 and washers F436. As one of the main a325 bolt suppliers, we can produce, stock and supply entire set of structural bolts and nuts, washers to support customers at the best.