This part of ISO 12137 specifies a method for determining, using a pointed stylus, the scratch resistance of a single coating of a paint, varnish or related product, or the upper layer of a multicoat system. Part 1 of ISO 12137 specifies a method using a curved stylus. The choice between the two methods will depend on the particular practical problem. This test has been found to be useful in comparing the scratch resistance of different coatings. It is most useful in providing relative ratings for a series of coated panels exhibiting significant differences in scratch resistance.