Black tanks live a harder life than gray ones - solids, chemicals, long intervals between dumps - and 42 gallons is the size where a black tank stops dictating your travel schedule. The 21H is one of Ronco's four 42-gallon holding shells: a single seamless rotomolded polyethylene body, 30 lb blank, roughly 350 lb when the full load is aboard.
Four shapes at one capacity is the Ronco pattern - the mold library grew coach by coach since 1974, so the survivors match real cavities. Here the dimensioned reference point is the 61H, a side-dump pan at 45 x 24.5 x 12 inches; the other two shapes are the 74H and 106H. The 21H's own outline is on the drawing below - print it and set it against your bay before deciding.
On the same printout, mark where your drain, vent, and inlet must land. Ronco installs fittings per order, spin-welded or threaded to those marks, at its Tustin, California plant - no guessing, no adapting your plumbing to someone else's hole pattern. Gray or black waste service only; the potable side of the catalog is at RV water tanks, and the full waste index at RV holding tanks.
OneSource Plastics is an authorized Ronco Plastics dealer.
Technical drawing: download the Ronco Plastics 21H 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.
Freight
LTL freight is quoted to your ZIP with the freight cost estimator or by phone at 866-418-1777. The listed price is before freight.
See this tank
Interactive 3D model with live fill. This tank has an interactive 3D model built to its manufacturer dimensions. Rotate it, and set a fill level to see how much liquid it holds at any height. Open the 3D view on the product photo above. Download the 3D model (GLB).
Ready to order?
Add it to your cart at the top of this page, get LTL freight to your ZIP, request a written quote, or call 866-418-1777. The listed price is before freight.
