The RVB433 is a dual-role molding: one large-capacity B-series tank that Ronco configures either as a fresh water tank or as a gray or black waste holding tank, depending entirely on the fittings you order. The blank is the same; the plumbing decision you make at order time is what it becomes. That flexibility is why B-series moldings show up in both marine and RV builds - one drawing solves two different systems.
Configured for fresh water, the FDA-compliant polyethylene resin is rated for potable service, and the translucent natural wall gives you a direct read on supply. Configured for waste, the same 120 pound molding takes on holding duty with the fitting set placed for drains, vents, and pump-out. Decide the role first - it drives every port location - then print the technical drawing below, mark your layout, and confirm it in the fitting planner on this page. Ronco spin-welds or threads each fitting to those marks at its Tustin, California plant, where it has molded tanks since 1974.
Whichever role you choose, respect the load: at 8.34 pounds per gallon, a full large-capacity tank is substantial, and it belongs low in the hull or chassis, fully supported. Light-duty wall schedule assumes exactly that kind of supported installation.
For the marine side of the family, see the boat tank category; for dedicated waste moldings, the RV holding tanks; for fresh-only footprints, the RV water tanks; and for the whole line, the Ronco Plastics hub. OneSource Plastics is an authorized Ronco Plastics dealer.