Description A white flat plastic scale ruler that is available in two grades with a coloured marking to be easily identified. The SRM6230 has a blue marking and has Ratios 1:1, 5, 10, 100, 20, 200, 50, 500 and SRM6330 with red markings has Ratios 1:1, 100, 20, 200, 25, 250, 50, 500.
