Abstract: A wafer-like insert has a plurality of holes therein which correspond to pins of an electrical connector. The wafer includes contacts for making electrical connection to the pins, connector shell or electrical components. In such manner, the wafer can be used for a wide variety of purposes such as conditioning signals carried by the pins and grounding selected pin(s) to each other and/or the connector shell. The wafer can be installed in any common electrical connector pair without prior modification or preparation of the connectors and without impairing the normal fit or function of the mated connector pair.