A Cornish Rex is a breed of domestic cat. The Cornish Rex has no hair except for down. Most breeds of cat have three different types of hair in their coats: the outer fur or guard hairs, which is about 5 cm long in shorthairs and 10 cm long in longhairs; a middle layer called the awn hair; and the down hair or undercoat, which is very fine and about 1 cm long. Cornish Rexes only have the undercoat. The curl in Cornish Rex fur is caused by a different mutation and gene than that of the Devon Rex. It originates from Cornwall, Britain.
The coat of a Cornish Rex is extremely fine and sometimes curly. Their light coat means that they are best suited for indoor living in warm and dry conditions, as they are sensitive to low temperatures. Cornish Rexes like to stay warm places such as computer monitors, light bulbs, laps and shoulders.