Coloured scanning electron micrograph (SEM) Cat hair (Felis silvestris catus). Cats have four types of hair. There are short fluffy hairs called secondary hairs. Other names for secondary hairs include underfur and undercoat. The second type is the longer and stiffer outer hairs called primary hairs. The primary hairs are also referred to as guard hairs, outer hairs, or outer coat. Cats, unlike some other mammals, also have hairs called awn hairs which are thinner than the primary hairs. Finally, whiskers are actually specially developed hairs, called tactile hairs, which help the cat sense her surroundings. Each hair shaft produced by a hair follicle will eventually die and be removed (shed) and replaced by a new hair shaft produced by that hair follicle. Cats continually shed old dead hair from the follicle and replace it with a new live and growing hair. Magnification: x220 when shortest axis printed at 25 millimetres.