... ,used at shock absorber and compensate for displacement.JGD mean single ball (arch),JGD-A dual ball ,JGD-B threaded rubber ... , we can do it for you!Material NO.NAMEMaterial1Inner and Outer GlueEPDM,NR,NBR,NEOPRENE2Key FrameNylon Cord Fabric3Pressurized RingSteel Wire Strand4FlangeQ235 ... ng .br> 6)When used on high building , Single Sphere Rubber Joint