O rings supplier in China? DMS Custom Rubber Rings, O Ring Company & factory covers an area of more than 10,000 square meters and the factory area is 8,000 square meters. Our production equipment and test equipment are at the leading level in the industry. We are one of the largest companies in China specializing in the production and development of seals. We have long-term communication and cooperation with many universities and research institutions at home and abroad. Discover extra details at o ring supplier. The O-ring seal, which is also called shaft seal, is noted for a reasonable compression …