The grassland rattleback is about the size of an otter. It is covered in an armor of thick protective plates used for defense which give it the appearance of an armadillo. The scales which form the plates are actually great mats of hollow hairs, similar to that of pangolins. The air trapped inside the hairs provides insulation against heat. Beneath the roof of scales, there is a layer of insulating pelt, and the animal has rows of spines along its flanks. The hairy plates are the rattleback's first line of defense against bushfires.