... NR, EPDM, etc 3.Different sizes Product NameRubber ball for valveCertificateISO9001:2008Country of OriginChinaAdvantagea. Ozone and chemical resistanceb. ... Qingdao City, China. We mainly produce the rubber products for a wide range of valves and pipes, rubber seals, auto ... standards,attractive design and durability. They are well-known for excellent quality, most competitive price, lowerlabor cost, ...