Abstract: A tubular adapter fitting for attachment to the service connector of a refrigeration unit enabling receipt of a quick disconnect coupler to attach the coupler end of refrigeration tubing in flow communication therewith. The fitting in comprised of a tubular body adapted at one end for mounting onto a service connector. A contoured periphery serves to receive a quick connect coupler almost instantaneously in a pressure tight interlock relation thereon. Two adapter fitting embodiments are disclosed, one of which is particularly suited to a threaded service connector of a type normally provided with the refrigerant unit of a vehicular air conditioning system. The second embodiment of the adapter fitting is more suited to servicing non-vehicular refrigerant systems in which a service connector is not normally provided in advance by the manufacturer of the equipment but must be provided by the serviceman on site.