Additional information and details on mechanical couplings are provided in Chapter 9 of the Plastic Pipe Institute (PPI) Handbook of Polyethylene Pipe.

Stab Type Fitting 

Stab type couplings are available for joining small diameter PE pipes (e.g., 2" IPS and smaller) to each other. There are several types of stab fittings of generally similar design concept, including an elastomer seal, such as an O-ring, and a gripping device to effect pressure sealing and pullout resistance. Self-contained stiffeners are included in this design. The operator prepares the pipe ends, marks the stab depth on the pipe, and "stabs" the pipe in to the depth prescribed for the fitting being used. These fittings are available in sizes from 1/2" CTS through 2" IPS and meet ASTM International D2513, Standard Specifications for Thermoplastic Gas Pressure Pipe, Tubing, and Fittings Category I requirements, indicating seal and full restraint against pullout.