The Ronco Plastics B491 fits 48 gallons into a 39 x 27.5 x 11.75 inch envelope, under a foot tall. That geometry targets the platform-and-plinth installs, under berths, under dinette seating, under raised RV floors, where capacity usually surrenders to furniture.
A dual-role B-series molding, the B491 becomes what its fittings say: potable fresh water tank in food-contact polyethylene, or gray or black waste holding tank, one shell serving either trade. In a tank this shallow the fitting layout is the whole ballgame, so Ronco installs everything per order, spin-welded or threaded to your exact marks, no factory-default ports to fight.
Full, expect about 400 lb of water at 8.34 lb per gallon spread across the wide footprint, atop a 95 lb tank. Print the dimensioned drawing below, confirm the height clearance with the lid or cushion in place, then finalize your ports in the on-page fitting planner.
Molded in Tustin, California by Ronco Plastics, founded 1974. The committed 48 gallon holding tank handles a decided waste role, low-profile alternatives live among the RV water tanks, and the freight cost estimator settles delivery. OneSource Plastics is an authorized Ronco Plastics dealer.
Technical drawing: download the Ronco Plastics B491 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.
