Abstract: A pipe coupling including a coupling body and swage rings for urging over the coupling body in order to secure the pipes together. The coupling body includes a main sealing tooth with an outboard isolation tooth and an inboard tooth located on opposite sides of the main sealing tooth. First and second grooves are defined between the main sealing tooth and the outboard isolation tooth and the inboard tooth, which grooves are of sufficient length and depth so that pipe secured by the coupling is not substantially deformed adjacent the first and second grooves in order to enhance the ability of the main sealing tooth to bite into the pipe in order to provide a hermetic seal and also to increase the resistance of the coupling to tensile loads. The outboard isolation tooth and inboard tooth protect the seal created by the main sealing tooth from external forces caused by bending. The main sealing tooth can include a twin tooth having a parent tooth and one or more sealing teeth extending therefrom.