Ko te rereketanga nui i waenga i te ngongo hau kōpeke me te ngongo hau kōpeke ko te huarahi e tautuhia ana te diameter.Ka inehia te ngongo ki te diameter o roto ka ine te ngongo ki te diameter o waho.Hei tauira, he 3/8” te ngongo hau kōpeke he 3/8 te diameter o roto.