rade 80 Alloy Chain is designed to stretch a minimum of 15% before it breaks, alloy chain is the only grade of chain approved by OSHA and other agencies for overhead lifting. Its alloy, heat-treated steel makes it ideal for making lifting slings and heavy duty tow chains. The manufacturer's symbol and grade marking: 8, 80, or 800 is placed on the chain links every foot or so. Grade 80 Alloy Chain is suitable for overhead lifting.