A pen-type weathering material that can be easily reproduced just by painting a three-dimensional stain expression. Ideal for expressing mud adhering to caterpillar tank models. Just turn the tip of the pen like a stick stick to get the color and just paint directly. Since it is water-based, it can be spread with a brush that contains water, and mud splashes can be reproduced. You can spread it with your fingers before it dries. Feel free to use it on the finished model and enjoy the dirty expression easily.