A wire connector is disclosed that has a removable cap to provide access to the connected wires for testing purposes. The connector includes a hollow body with a wide end and a narrow end, openings to the interior of the hollow body in each end, an electrically conducting spring inserted inside the body, and a cap threadably receivable on the narrow end of the body. The cap has a plug that fits into the hole in the narrow end of the body to limit the advance of the electrical conductors inserted into the wire connector. The spring in the body has a neck that operates in combination with the cap's plug to limit conductor advance. The cap can be made in colors different from that of the body so that it can serve as a code to identify the circuit to which the wires belong. The cap may be formed with different styled surface features that help gripping. The style of the surface features may be matched to the preference of the user since the caps are interchangeable.
