Pluggable connector with differential pairs

A pluggable connector that includes a housing having an inner surface that defines a housing cavity. The housing cavity extends along a central axis to an opening of the housing cavity. The opening is sized and shaped to mate with a mating connector moving along the central axis. The connector also includes a plug insert that is positioned within the housing cavity. The plug insert extends along the central axis and forms contact cavities therein that extend parallel to the central axis. The plug insert has an outer surface that is separated from the inner surface of the housing by a spacing. The connector also includes differential pairs. Each differential pair has two mating contacts that extend parallel to each other along a contact plane of the differential pair and within corresponding contact cavities. The contact planes of at least two adjacent differential pairs are perpendicular to one another.