Abstract: An adapter assembly for connecting a sewage drain pipe to a sewage disposal site inlet in fluid communication includes a hollow tubular member, a hollow adaptive member and flexible seal. The hollow tubular member having an open inlet adapted to engage threadable or otherwise to the end of a sewage drain pipe. A hollow adapter member having an open discharge end with adaptive features to be inserted into disposal site inlet. The tubular and adapter member interfacing via a rotational positive mechanical lock compressing an annular flexible seal radially or axially to ensure a dependable, long lasting low pressure fluid tight seal.