What Is the Difference Between A2-70 and A2-80 Property Classes? A2-70 is a standard strength class for A2 stainless fasteners. A2-80 has higher tensile strength and is used when the project specification requires greater fastening strength. By Marsh Fasteners|2026-07-10T03:14:48-04:00July 10, 2026|A2 Stainless Steel Metric Socket Head Cap Screws|