3-layers:
1.Pex inner layer 2.Adhesive layers 3 Evoh oxygen barrier layer

The Advantages:

1.Corrosion,especially resistance to electrochemical corrosion
2.Low heat dissipation and friction loss
3.Thermal memory
4.Quiet water flow
5.Nontoxic and safe
6.Nontoxic and safe
7.Flexibility for easier and faster installation
8.Fewer fitting for less chance of leaks
9.Arractive installation costs
10.Quiet operation.
11.Oxygen resistance