Currently, there are five standardized coat types, which are commonly referred to as varieties. These are rex, satin, hairless, tailless, and standard. Lets describe each of these types. The rex rat has curly hair, and curly whiskers. The coat of a rex rat can be long hair with waves or short hair with tight curls.
Males tend to have the curlier coats, while females have the waves.
As the name says, a hairless rat is completely hairless. Patchwork hairless rats have little patches of fur that falls out and grows back in other places, often making the rat look different each week. Tailless rats would be expected to be more popular with the rat tail-hating people, but they are not very common.