It really does look like dirt. One quick spray makes models look weathered. One of our most effective, highest selling colours. Works really well on its own or mixed with any of the other colours, particularly Slate Grey. If you are buying just one spray, then make it this one, or Oil Brown.
On grass, tree and shrub foliage Mud Brown looks a dark muddy colour. In our opinion it's one of the best sprays for use on ballast, rails and sleepers, creating a really muddy/dirty finish. Wipe it off the top of the rails using a damp tissue after it has dried. Also very effective on roads and platforms.
Mud Brown looks like mud when applied to model houses and trains. We use it on almost all our models.