The smallest tank in this group is also the easiest to say yes to: the Ronco Plastics B495 holds 10 gallons, weighs 17 lb, and tucks into voids most builders write off entirely, the nose of a cuddy, the gap beside a wheel well, the back of a galley cabinet.
Small does not mean single-purpose. The B495 is a dual-role B-series molding: fresh water fittings make it a compact potable tank in food-contact polyethylene, ideal as a dedicated galley or washdown supply; waste fittings make it a day-use gray or black holding tank for the smallest heads. Ronco installs your fittings per order, spin-welded or threaded at marked positions, a service that matters even more at this scale where every port must clear something.
Full, it holds about 83 lb of water at 8.34 lb per gallon, a load almost any sole or shelf can take with basic fastening. Print the drawing below, confirm the void really fits it, and set your ports in the on-page fitting planner.
Molded in Tustin, California by Ronco Plastics, in the business since 1974. See the 10 gallon holding tank for the committed waste version, or the broader marine tank collection for the next sizes up. OneSource Plastics is an authorized Ronco Plastics dealer.
Technical drawing: download the Ronco Plastics B495 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.
