A Closure Fitting is a special coupling configuration for joining both Carrier and Containment piping in situations where opposing runs of Carrier and Containment system must meet. Closure Fittings are frequently used at the end of a system where the final Termination Fitting must connect to a fixed point in the system. Spears® offers a complete range of Solvent Cement Closure Fittings that form a permanent solvent cement joint, plus special Union Closure Fittings in limited sizes that provide an easily-installed union to join these opposing Containment piping runs. See Double Containment Design and Installation Guide for proper installation. Solvent Cement Closure Fittings consist of a male component and a female component. An internal O-ring on each component serves as a "cement-wiper" during installation to assure a proper joint. A "One-step" type cement, such as Spears® CPVC 24 for both PVC and CPVC, should be used to facilitate rapid assembly. See Double Containment Design and Installation Guide for proper installation.