In 1941, the SAE Iron and Steel Division in collaboration with the American Iron and Steel Institute (AISI) made a major change in the method of expressing composition ranges for the SAE steels. The plan, as now applied, is based in general on narrower ladle analysis ranges plus certain product (check) analysis allowances on individual samples, in place of the fixed ranges and limits without tolerances formerly provided for carbon and other elements in SAE steels (reference SAE J408).