... , reduced rubber joints, rubber elbows, fan coil joint, sewage check valve rubber, rubber filter, rubber compensator air flue compensator, flexible ... rubber shock pad, shock absorber, pipe damper, seal, gate valve,check valve, foot valve, filters, valves, pressure balance valve, valve, ... ,used at shock absorber and compensate for displacement.JGD mean single ball (arch),JGD-A dual ball ,JGD-B threaded ...