A multipole plug 1 is configured in such a manner that a first terminal strip (first terminal strip 15) is provided with first flow holes (second flow holes 15D) in a first curved plate portion 15B, a second terminal strip (second terminal strip 17) is provided with a second flow holes (third flow holes 17D) in a second curved plate portion 17B, and the first curved plate portion 15B and the second curved plate portion 17B are positioned by the positioning ring 20 provided with an outer projecting portions 20B to be fitted to notched portions 18F of a first sleeve portion (second sleeve 18) and an inner projecting portions 20C to be fitted into a gap between the first curved plate portion 15B and the second curved plate portion 17B being fitted thereto.