Next time you are drawing up a metric Bill of Materials (BOM) for a non-critical assembly, save your budget for the high-strength bolts where they matter, and specify for everything else.

Here is everything you need to know about this critical standard. ASTM A307M is the standard specification for Carbon Steel Bolts, Studs, and Threaded Rods (Metric) . It covers three distinct grades (A, B, and C) intended for general engineering and structural applications.

Understanding ASTM A307M: The Workhorse of Metric Bolting

While the imperial version (A307) has been an industry staple for decades, the standard is its metric counterpart, specifically designed for projects operating in the SI (metric) system.