Three gallons. The 13W is the smallest kind of honest: a 17 x 7 x 7 inch sleeve of polyethylene for the jobs where a big tank is the wrong answer - a camper van sink, a tool-trailer handwash station, a teardrop galley, a slide-in cab-over where every inch is spoken for. It slips behind a wheel well or under a cabinet floor and disappears.
Because it belongs to Ronco's dual-role Water / Waste series, the same little molding can be ordered as a fresh tank - FDA-compliant resin, safe for drinking water - or fitted as a compact gray-water catch under that same sink. At 6 lb empty and about 25 lb full (8.34 lb per gallon of water), it is the rare tank you can mount almost anywhere without an engineering discussion.
Need more capacity in the same spirit? The RV water tank range runs from this size up to triple-digit gallons, and the full Ronco lineup includes the marine and holding versions of nearly every shape.
Molded in Tustin, California by a shop that has done custom water tanks since 1974. Fittings go in per order - spin-weld or threaded, exactly where you mark them: print the drawing below or use the on-page fitting planner. OneSource Plastics is an authorized Ronco Plastics dealer.
Technical drawing: download the Ronco Plastics 13W 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.
