A mated connector assembly includes: a first connector assembly, comprising a plurality of first coaxial connectors mounted on a mounting structure and a first shell; and a second connector assembly, comprising a plurality of second coaxial connectors, each of the second coaxial connectors connected with a respective coaxial cable and mated with a respective first coaxial connector. The second connector assembly includes a second shell surrounding the second coaxial connectors, the second shell defining a plurality of electrically isolated cavities, each of the second coaxial connectors being located in a respective cavity. In in a mated condition the second shell resides within the first shell.