A wolf's coat is remarkable, a luxurious fur consisting of two layers: a soft, light-colored, dense underfur that lies beneath a covering of long guard hairs. The guard hairs shed moisture and keep the underfur dry. Much of the underfur and some of the guard hairs are shed in the spring and grow back in the fall. The coat is thick across the shoulders, where guard hairs may be 4-5 inches long, and thins out on the muzzle and legs.