ISO 185:2005 specifies the properties of unalloyed and low-alloyed grey cast irons used for castings, which have been manufactured in sand moulds or in moulds with comparable thermal behaviour. ISO 185:2005 specifies the characterizing properties of grey cast iron by either the tensile strength of separately cast samples, or if agreed by the manufacturer and the purchaser, of cast-on samples or samples cut from a casting, or if agreed between the manufacturer and the purchaser, the hardness of the material measured on castings or on a cast-on knob.