... -way check valves) 2.Material:Silicone,FKM rubber,Fkm-silicone,NBR Duckbill Valve ItemDuckbill ValveBrandRAMISCountry of OriginXiamen, ChinaItem No.RS70110Opening pressure0.3-55kPaMaterial ... according to ASTM, DIN, SAE,VDA6.1, UL, FDA, JIS . Duckbill valve