PURPOSE: To easily manufacture a dispersion header and a flexible pipe of a steel pipe on the market, and provide flexibility at a connection part.

CONSTITUTION: One end part of a main body 2 composed of a pipe material is closed with a cap 4, plural through holes 13 are bored in the outer circumference of the main body 2, and a branch connection pipe 11 having a flange part 12 which is tapered to open at one end is fixed to a circumferential edge part of the through hole 13 to fix a branch connection body P1 to which a flexible pipe for connection is connected. All the component members can thus be manufactured of the pipe material, and by butting a ball seat part of the flexible pipe for connection against the flange part 12 through an O-ring, and fixing them at a housing on the outer side, water-tight connection having flexibility can be easily realized.