To reduce the size of a body by minimizing increase in component shape by keeping of draft in a component.

Water supply passage members 22a, 22c of a water supply system 50A and a water discharge passage member 22b of a water discharge system 50B are provided separately from a body 21. In this example, the maximum inside diameter point P2 at the other end of a body internal passage 21a' with a preset draft of about 1 from the minimum inside diameter point P1 (7 mm) is formed about 12 mm. On the other hand, the minimum inside diameter point Q1 at one end of the passage member 22a with a preset draft of about 1 from the minimum inside diameter point Q1 (7 mm) is formed about 8 mm.