A receptacle RF connector includes an outer shell having a third unsealed tubular frame, at least a cutout is defined around the third unsealed tubular frame and runs through a lower periphery downwardly, each cutout has an upper periphery and is located under a locking tuber correspondingly, the upper periphery of each cutout keeps a predetermined distance with a top face of the dielectric block, so as to avoid the overloaded stress loaded on the receptacle RF connector caused by the plug RF connector.