The flex coupling can join: 1)the ductile iron pipe 2)cast iron pipe 3)steel pipe. 4)high quality and competitive price Description of the flex coupling in details:1) One middle ring with beve ends, epoxy coated2) Two follower rings, epoxy coated3) Complete set of bolts, nuts and gaskets.4) Specifications: type: AB-CD, AC-DI, AC-Stl, DI-Stl size: 2", 4", 6", 8", 12", 16" 5)Punctual delivery.6) ...