ASTM A193 Grade B7 all thread rod is manufactured from an alloy which includes chromium-molybdenum steel, quenched and tempered, for added strength and corrosion resistance. All thread rod listed below is melted and manufactured in the USA where specified domestic. Dimensional specifications are governed by ASME B18.31.3. Inch series fasteners meeting ASTM A193 Grade B7 specifications are typically used in flange bolting applications. ASTM A193 covers the requirements for high temperature and high pressure bolting.