Ronco RV Holding Tanks

Ten gallons in a slim 25.25 x 12.75 x 8 inch bar: the Ronco Plastics B389 slides into chases and narrow lockers that reject anything squarer. Camper vans, small sailboats, and skoolie builds use this...

The B533 is 4.25 inches tall. Not much taller than a closed fist - and inside that sliver, 27 inches long and 13.25 wide, it still keeps 6 gallons. This is the thinnest molding in the marine B-series...

The B325 is the shape you reach for when the space you have is a box, not a slot. Its 17 gallons sit in a 19.5 x 18 x 12 inch molding that is nearly square in plan - a proportion that fits...

Thirteen gallons is an honest weekend of gray water for two people, and the 26H is Ronco's compact way to carry it. At 16 lb out of the mold it is an easy tank to handle solo through a retrofit, and...

Twelve by twelve, 32 inches long: the 27W is a beam of a tank. Its square section is the detail that matters - a 12 inch cube profile drops into cockpit lockers, settee bases, and the square voids...

The B265 stacks 14 gallons vertically: 17.5 x 14.5 x 14.25 inches, a compact block that uses height instead of floor. In a cockpit locker or a van's kitchen pod, that trade is the difference between...

The B510 is close to a cube: 42 gallons in a 24 x 22 x 20 inch block. That proportion is the whole argument for it. A near-cubic tank puts the most volume behind the least surface area, so the walls...

At 20.75 x 17.75 x 13.75 inches, the B227 is barely bigger than a milk crate - and it holds 20 gallons. That compactness is a genuine trick: most 20 gallon moldings buy their volume with length, but...

Fourteen and a half inches wide is the number that gets the B231 into boats and vans that reject wider tanks. At 28.25 x 14.5 x 11.5 inches it is a slim 20 gallon molding drawn for the corridor...

The B450 is the slim sibling in Ronco's long-tank family: 23 gallons at 44.5 x 12.5 x 11.5 inches, a cross-section barely a foot square stretched to nearly four feet. When the only unclaimed space...

The 41H is built around its outlet: a 12-gallon holding tank with a side dump, meaning the waste valve exits the sidewall rather than the bottom. On rigs where there is no clearance below the tank...

Sixteen inches on every axis. The B106 is a true cube - 16 x 16 x 16 - holding 16 gallons, and the symmetry is not a party trick: a cube fits any orientation, so the same tank drops into a boat...