PURPOSE: To eliminate brazing, and facilitate connection between a mixing faucet and a water supply pipe by providing projecting pipes fixed with a flange to the end faces of inlets of the mixing faucet, and arranging the water supply pipe connected to the projecting pipes and joint pipes to the other side.

CONSTITUTION: Two projecting pipes 11 and 11 inserted into two inlets 2 and 2 of a mixing faucet 1 are provided to one side, and outside diameters of the projecting pipes 11 are fitted to inside diameters of the inlets 2. O rings are provided between the projecting pipes 11 and inlets 2 to seal, and a flange 12 is monolithically connected to the projecting pipes 11 to fix to the end faces of the mixing faucet 1 with screws. In addition, a water supply pipe and two joint pipes 14 and 14 for connection are provided to the other side. According to the constitution, replacement work of the mixing faucet 1 can be also carried out easily.