A connector assembly for installation on a wall includes a main connector body introduced into a cut-out hole of the wall and a protective shell positioned on an inner side of the wall. The protective shell protects the main connector body from an insulation foam entering the main connector body when foamed in place. The protective shell has a front portion, a receptacle formed at the front portion and receiving a second end of the main connector body, a flange extending from and surrounding the receptacle, and a lead-through channel formed at a back portion of the protective shell. The flange is attached on the inner side of the wall and covers the cut-out hole. The lead-through channel has an internal flap routing a cable through the back portion in a meandering manner. The internal flap is inclined with respect to the lead-through channel.