The color codes are going to look like this for these jacks. These terminations are called "IDC" for "insulation-displacement connections," by the way, since the wires are held in knife-edge terminations that slice through the insulation and dig into the copper wire, forming a tight seal. Characteristic impedance MHz. Sometimes there are cross connects using punchdowns in the telecom closet, more common on telephone wires than data. Cat 3 jacks and all plugs are going to use these color codes shown above. It is important to keep all cables neatly bundled and labeled so they can be moved when necessary.