Certa-Lok C900 RJIB (for “restrained joint integral bell”) features the company’s standard mechanical joining system of precision-machined grooves and nylon spline for tensile strength in pulling/pushing, but ensures a pressure-certified hydraulic seal by adding a flexible elastomeric gasket within an integral bell. The restrained-joint PVC pipe doesn’t require fusion or solvent welding. It can be assembled in real time as pullback continues, eliminating the need to string out several hundred feet of pipe within or beyond the work zone. Available in 4-, 6-, and 8-in. diameters.