A connector system is disclosed that can support high data rates over a connector with terminals on a 0.5 mm pitch. A plug connector can include a termination module that has a paddle card and a plug module that includes rows of terminals. The termination module and the plug module can be aligned via the row of terminals and pads on the paddle card. A receptacle connector includes two rows of terminals that are provided on opposite sides of a tongue. The tongue includes impedance notches aligned with terminals arranged as differential pairs. Ground terminals extend past the differential pairs and along the impedance notch.