All units are welcome to choose the soild O-Ring Cord, O-ring Nbr, resistance to high temperature rubber ball produced by our company. We are willing to cooperate with you loyally and develop together! Zhonggao Seal Technology is one of the leading Oring manufacturers and suppliers in China. Our factory has a wide varieties of Oring products in stock. Please be free to buy the bulk products from us. And we will also offer the customized service if necessary.