... plastic composite pipes(PEX-AL-PEX pipe) for cold/hot water supply:1, Non-toxic, corrosion resistance,light weight, good mechanical ... small, not easy scaling, fluid not being polluted, and effective large diameter. 3, 100% insulating oxygen,stop oxygen's penetration. Aluminum ... .2319.52632500.2313.0 pex-al-pex pipe for hot water supply