Abstract: A pipe fitting for rubber hoses, of the type with a thermoplastic substrate, particularly for air conditioning, conditioning and refrigeration systems, particularly for vehicles and the like, comprising a rigid insert which is adapted to be inserted in a hose to be connected, and a bell-shaped element which is adapted to be crimped around the hose, its particularity consisting in that it comprises a double-adhesive solution which is arranged on the outer surface of said rigid insert and is adapted to produce adhesion between said rigid insert and said thermoplastic material of said internal layer of the rubber hose.