Adopt "Insulation Displacement Connection " technology; Double-layer, double-contact folding IDC contacts; Test cord and patch cord are provided for cord patching, on-line test and self-loop test; Wrapping-connection type structure with strong anti-pull-out force; The data pins and grounding pins are glided and silver-gilt respectively to distinguish from each other; Low contact and terminal resistance is convenient for multiple-connection and test; Cables of a, b and s are arranged in one module, and the stripped length of shielding coat is short so as to improves the crosstalk ratio among lines; 19 inch structure with large capacity and high density;