Hydro 4000 Hydrogen Generator / HHO Fuel Cell Canister - Used

Hydro 4000 hydrogen generator / HHO electrolysis canister — an aftermarket universal-style fuel-saver accessory used on diesel and gasoline engines, gensets, trucks, and equipment. Green steel canister with DC electrical terminal studs, gas-outlet hose barb, top fill/relief fitting, and bottom drain knob. Application not verified — sold by photographs, identifiers, and dimensions; this is not an OEM engine service part and no fuel-economy, emissions, or performance claims are made. Condition: used take-off, untested. Chipped/scuffed paint, torn caution decal, cut wiring pigtails; no harness, controller, or mounting hardware included. Not opened, powered, pressure-tested, or flow-tested. The canister will be drained and its ports capped before shipping. Buyer must confirm fitment by part number, photos, dimensions, engine model, serial number, and application before purchase. Used marine part sold as-is unless otherwise stated. No returns on electrical, used, special-order, or installed parts.