rubber o ring 1.Best service and short delivery time 2.Best quality with reasonable price 3. certificate: ISO, SGS rubber o ring 1. available material: NBR, FPM, FKM(VITON), HNBR, SBR, CR, EPDM etc.2.customer's design and specifications are accepted.3.color and shape can be changed upon request.4.our professional R&D team can provide you higher quality products with competitive price 5,responds ...