This vinyl double containment piping system is fast and easy to install, and is available with a complete selection of pipe, fittings, leak detection and access tees, closure couplings and termination fittings. Additionally, an innovative ?valve-in-valve? design is offered which allows full containment pressure rating. Double-See is available in PVC and CPVC; either material may be primary or secondary (PVC × PVC, CPVC × PVC, CPVC × CPVC) with Clear PVC always being an option for the containment pipe. System size options range from ½" x 2" to 6" x 10" meeting virtually any application requirement. Installation versatility allows simultaneous joining throughout a system or in combination with patented closure couplings which enable practical compliance with the ASME B31.3 requirement for visual inspection of all primary joint connections during the pressure test before closing the secondary piping joint.