Form S71 is a black and white painted strip. It's black on the left, white on the right, and measures 2 x 11 inches (51 x 279mm) overall.
These jams are used primarily in the automotive industry, including refinish operations, when evaluating the hiding power of spray-applied coatings. The chart is usually attached to a steel or aluminum plate and sprayed with a test coating to create a "wedge" that is thin at one end and thick at the other. After drying, identify a location on the cardboard with sufficient visual coverage (typically a contrast ratio of 0.98) and measure the film thickness of the coating on the metal plate adjacent to that location. Instead, the location of the specified thickness is identified on the metal panel, and the contrast is measured near that location.








