Abstract: A fitting connectable to an end portion of a pipe generally includes a tubular insert member configured to be received at least partly within the end portion of the pipe, and a retention member coupled to the insert member and configured to be received at least partly within the end portion of the pipe. The retention member operates in conjunction with the insert member to engage the end portion of the pipe and impart an increased force against an inner wall of the pipe in response to forces tending to separate the fitting from the end portion of the pipe. The insert member includes a plurality of reinforcement ribs formed on its inner surface which provide support to the insert member and help prevent damage thereto from transverse bending forces applied during installation.