5 layers cosmetic tubes(EVOH tubes/CO-EX tubes) are with EVOH, while single/double layers tubes are without.
Below picture for refer the structure of 5 layers tube.
5 layers tube ( Multi-layer cosmetic tubes/EVOH tubes/CO-EX tubes )has the stronger isolation , it is good for the sunscreen products , foundation, medicines or some cosmetic which has the special ingredients , alcohol and special odour and fragrance.
Double layers tube can be used for the facial cleanser, facial cream, hand cream and body lotion and so on.