The DHT-L series tanks are pre-assembled holding tank systems that come in 5 popular tank sizes. Available capacities are 11,16,23,29,36 gallons, they are pre-plumbed with inlet and discharge fittings, a vent fitting, an inspection port, and a pressure relief valve. Each tank is pressure-tested and ready to install. The tanks are made of high strength polyethylene with a heavy-duty wall thickness of 0.25 inches to maintain integrity even under high pressure, and avoid permeation of the tank wall with waste odor. The inlet & discharge fittings accommodate 1.5 inch ID sanitation hose but can be adapted to other plumbing system dimensions.