... ,used at shock absorber and compensate for displacement.JGD mean single ball (arch),JGD-A dual ball ,JGD-B threaded rubber ... , shipping, pumps, compressors, fans and other piping systemsbr> [Media]:Common type used to transport -15 to 120 centigrade, of air, compressed ... air, water, sea water, oil, acid and alkali. Special type used to transport -30 to 250 centigrade of the medium ...