Big diameter butt-welding plastic pipes, with available diameters: 16, 20, 25, 32, 40, 50, and 63mm Aluminum-plastic pipes ... more and more popular in the building.Features: 1) Specification: Φ16 - 63 2) Non-toxic, anti-corrosive 3) Light weight, strong ... happen 6) The fluids cannot be contaminated. Effective diameters are big 7) Oxygen is 100% isolated and infiltration is thoroughly prevented ...