The Nut,flange,6mm is the most widely applied product in the CN250 HELIX 1992 (N) USA WATER PIPE ( four times ).
Some items from this specific schematic: Pipe Comp.,l.wate, Bolt,flange,6x40, Pipe,floor Panel, Nut,flange,6mm.
The lowest price component in this Water Pipe parts-list fiche is the Nut,flange,6mm.