Federal Standard 26231 is a gray color equivalent to British Standard (BS) 638. This color is perfect for RAF aircraft since 50’s but also useful for other subjects such as ships, mechas, or other Sci-fi.Authentic color formulated for maximum brush & airbrush performance with the Scale Reduction Effect that allow us to obtain the correct colors in model kits. 17ml jar. Water soluble, odorless, and non-toxic. Shake thoroughly before each use. We recommend A.MIG-2000 Acrylic Thinner for thinning. Dries completely in 24 hours.