The Poly-Flo&reg Unitary Double Containment Piping System is ideally suited for the transport of aqueous ammonia used in new water treatment disinfection processes. The Poly-Flo double contained piping system is compact, affordable and as easy to install as a single wall pipe system, due to its unitary construction design. The Poly-Flo system has a unitary extruded design and is constructed of polypropylene and high-density polyethylene (HDPE) materials. A complete line of molded fittings, as well as special order fabricated fittings for drainage or pressure applications are available in all size configurations offered. Poly-Flo&reg is available in sizes 1×2, 2×3, and 4×6. Patented double O-ring flanges allow Poly-Flo&reg systems to be efficiently pre-assembled, then easily bolted into place in the field.