A duplex cable connector assembly including a connector body with an insert and spring clip including a first free end for engaging a side wall of an electrical box upon installation. The insert provides both a sleeve insulator at an end of the connector assembly and a cable divider portion to guide and separate cables. During insertion of the connector body the first free end is deformed so as to permit further insertion into the electrical box. Once the connector body is fully inserted, the spring clip cooperates with a lug on the connector body to hold the connector assembly onto the electrical box.