AS 1004.2-1998 pdf free.Surface Plates For Metrology - Part2:Granite. This part of ISO 8512 specifies requirements for rectangular or square granite surface plates ranging from 160 mm x 100 mm to 2500 mm x 1600 mm, as preferred sizes, in four grades of accuracy 0, 1, 2 and 3. NOTE 1 Granit& is a commonly used description; a more specific...