The B564 is the B-series molding with its footprint on the label: 28.75 x 19.75 x 11 inches, 24 gallons. That 11 inch height is the story - this is a flat tank, built to disappear under a berth, a cockpit sole, or a settee base where a taller shell simply will not go. Measure your clear height first; if you have a foot, you have room.
Like every tank in the series it is dual-role: ordered with fresh-water fittings it is FDA-compliant potable polyethylene, ordered for holding duty the same shell carries gray or black waste. Full, it holds about 200 lb of water spread across that wide, low footprint - a favorable shape for load spreading, but still one that deserves a flat, supported bed rather than a pair of stringers under the ends. The blank ships at 26 lb.
Fittings go on per order at Ronco's Tustin, California plant - spin-welded or threaded to your marks, the same way since 1974. Low tanks are picky about penetration placement, so print the drawing below, think through where the pickup must sit to drain the last gallons, and lay it out in the on-page fitting planner.
More low-profile shapes live under boat tanks and RV water tanks; the full catalog is on the Ronco Plastics hub. OneSource Plastics is an authorized Ronco Plastics dealer.
