... key prestigious projects, and exported to the U.S., Germany, Italy, Japan, Korea, Egypt, Spain, Vietnam and other countries, ... character of "Forward flow, reverse Check" new type water drainage product.Depend on pressure analysis and stress calculatioin,for ... 5250200225270200401503204727534026527536026550200375197338420325338450325502504752474005204254005604257530056Water Treatment Rubber Back Valve