The Ronco Plastics B184 is 25 gallons of deliberate ambiguity: a marine water / waste series molding that becomes whichever tank your boat is missing. Order it with potable fittings and it is a fresh water tank in FDA-compliant polyethylene; order it with waste fittings and it is a 25 gallon gray or black holding tank - a capacity that comfortably covers a weekend of heads and sinks on a mid-size cruiser. One shell, one drawing, two entirely different problems solved.
The decision lives in the fittings, and the fittings live where you put them: installed per order, spin-welded or threaded at your marked locations. A water build wants the pickup at the drain-dry point; a waste build wants the outlet at dead bottom and an honest vent. Print the drawing below, mark the version you are commissioning, and run it through the fitting planner on this page so what arrives matches what you meant.
The tank ships at 36 lb and carries about 208 lb of water at capacity - size the platform and straps for the contents, not the box it arrived in. Molded in Tustin, California by a company doing exactly this since 1974. Fresh-water context is at boat tanks, holding-tank context at RV holding tanks, and the full Ronco range at the Ronco Plastics hub. OneSource Plastics is an authorized Ronco Plastics dealer.
Technical drawing: download the Ronco Plastics B184 dimensional drawing - print it to plan your install and mark exactly where you want fittings located; Ronco installs spin-weld or threaded fittings to your marked spec.
