Product Description FOUR COLORS AVAILANLE : RED ,ORANGE ,GALVANIZED ,BLUE Specifications ductile iron Flexible coupling / fire fighting / grooved fittings 1.FM UL approved  2.Size:1-12″  3.Material:ductile iron  4.Surface :painting,epoxy,hot dip galvanzed Ductile Iron Rigid Coupling                                      UL FM … Continue reading China high quality FM UL Approved 3″ Cast Iron Blue Flexible Grooved Coupling