Abstract: An electrical connector includes a housing, and first and second contact modules mounted proximate one another in the housing. The first and second contact modules each include a mating edge and a mounting edge, and the first and second contact modules each include a lead frame having terminals extending between the mating edge and the mounting edge. The first and second contact modules each encase corresponding terminals, and the first and second contact modules each have contact side surfaces that face one another when mounted in the housing. The side surface of the first contact module includes a void positioned therein and exposing the lead frame, and the side surface of the second contact module includes a protrusion extending outward therefrom. The void and the protrusion are aligned with one another such that the protrusion is received in the void when the first and second contact modules are mounted in the housing.