The B538 is the stretched version of Ronco's compact near-cube marine tank: same 22-inch width, same 20-inch height, drawn out to 26 inches long for 45 gallons. If you measured a compartment for the shorter molding and found 2 inches to spare, this one converts them into 3 more gallons - the kind of increment that matters when tankage is the limit on how long you stay out.
It is a dual-role B-series molding, so one blank covers both jobs: fresh water service in FDA-approved potable polyethylene, or gray/black holding service, decided entirely by the fittings you order. Ronco installs them to your marked locations - spin-welded or threaded - before the tank leaves the plant. Print the drawing below, mark fill, vent, and pickup where your plumbing runs, and lock the layout in the fitting planner on this page.
Full, the B538 holds about 375 lb of water against a 37 lb shipping weight, and its blocky proportions carry that stiffly - short wall spans, no broad flat panels. Give it a floor, strap it against surge, and it is done. Molded in Tustin, California, on a production line running since 1974.
The rest of the mid-size marine range is in our boat tank category; see also RV water tanks for land-side formats, and the Ronco Plastics hub for the complete catalog. OneSource Plastics is an authorized Ronco Plastics dealer.
Technical drawing: download the Ronco Plastics B538 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.
