BS HR 650:1972 Specification for high expansion heat-resisting steel bar and wire for the manufacture of bolts, studs, set screws and nuts (Ni 25.5, Cr 15, Ti 2, Mn 1.5, Mo 1.25, Si 0.7, V 0.3) (limiting ruling section 20 mm)

standard by BSI Group, 04/07/1972