Ronco Plastics

The 100H is the tank you buy when the holding tank that died was an odd one. Ten gallons is the working size for pop-ups, truck campers, and small travel trailers, and Ronco Plastics molds a whole...

Thirty-five gallons of gray or black water is not a small load: full, the 101H is carrying roughly 292 lb of waste, which is why this tank is rotomolded as a single seamless piece of waste-rated...

The 102H comes from the newest chapter of Ronco's tooling - the 100-series molds - applied to the oldest job in the catalog: 20 gallons of waste holding. Later-generation molds reflect what five...

The 103H is the heavyweight of Ronco's four 40-gallon holding shells - 50 lb of polyethylene before a drop of waste goes in, against 28 to 33 lb for its capacity twins. Ronco molds the same volume in...

Start with the drawing on this one. At 16 lb empty the 104H sits at the light end of the 15-gallon class, easy to trial-fit repeatedly through an access hatch. Full, it carries about 125 lb of gray...

Mold number 105 tells you something before the specs do: this is one of the late additions to a holding-tank library that Ronco has been expanding since 1974, cut because installers kept hitting a...

The 106H carries the highest mold number in Ronco's holding library - one of the newest additions to a collection that has been accumulating in Tustin, California since 1974. New molds get cut for...

The 10H is the straightforward box of Ronco's 22 gallon holding tank family: 34 x 22 x 12 inches, no exotic proportions, the shape a coach builder reaches for when the compartment is a plain...

If you sketched a generic RV holding tank from memory, you would draw something very close to the 11H: 37 x 20.25 x 11.5 inches, a proportioned rectangle that fits the classic under-floor waste bay...

The 11W is a near-cube: 21 x 13 x 13 inches, 14 gallons. Where most RV tanks chase length to hide under a floor, this one goes the other way - deep and compact, sized for a vertical locker, a bench...

The 12H goes deep instead of wide: 18 gallons in a 22 x 23 x 12.5 inch cube, the deepest draw in its capacity class. A tank like this occupies a compact square of floor - barely two feet on a side -...

Twenty gallons is the most contested size in Ronco's holding line - the maker keeps roughly a half dozen distinct 20-gallon molds in production because that capacity maps to more RV floor plans than...