The RVB356 sits near the top of Ronco's light-duty B-series fresh water range, a 133 pound molding for builds where water capacity is the mission: full-time rigs, crew trailers, mobile grooming and wash setups that live or die by how much they carry. When a tank gets this large, the drawing stops being reference material and becomes the design document - print the one below and lay your whole water system out on it before you spend a dollar.
Like every tank in the series, it is molded in translucent natural polyethylene from FDA-compliant resin, so it is rated for drinking water and shows its level through the wall. Light-duty means the wall schedule is matched to supported, in-vehicle fresh water service; it is not a claim about fragility. Ronco has molded B-series tanks at its Tustin, California plant since 1974, and long-running tooling is why the fit is predictable part after part.
Fittings are installed at the plant to your order - spin-welded or threaded, at the locations you mark. Use the fitting planner on this page to place fill, vent, and outlet where your plumbing actually runs, and remember that water at 8.34 pounds per gallon makes a full tank of this class a serious static load. Put it over structure, low in the chassis, and the rig will thank you.
The RV water tank category covers the smaller stock sizes, the Ronco Plastics hub shows every family in the line, and the freight estimator turns this tank's shipping into a real number for your ZIP. OneSource Plastics is an authorized Ronco Plastics dealer.