Who knows what raw materials are used for the wide water pipes in Germany?

There are many top ten ppr rankings on the Internet that are not authoritative. In fact, there is no such definition in China, but the PPR water pipe was actually invented by German Guo Sheng. The material of Kuansheng is an exclusive patented invention (brass fittings, excluding nickel and chromium) that meets the highest drinking water standard in Europe. At present, the inside information I know is that only Kuansheng is produced by the original factory in Germany. What other water purification and Pierce are just agents, the factory production is opaque, and water purification does not have its own factory.