check valve 1.Standard: IS09001:2000 2.High-pressure,high-temperature,corrosion resistance 3.Rubber:EPDM NBR. check valveThis valve is our special product, ... America, it is usually named as duck mouth-shaped valve. This product is the further technology development and design ... , reservoirs, and so on. Indeed, it is environmental friendly valve because it solve the problems of block by the sediment ...