The Toyota 15.13 is a wiring harness, enables the Unichip to be installed without cutting or tampering with the original wiring harness of the vehicle. You simply unplug the ECU wiring and install the harness between the male and female plugs.
All the necessary original male and female plugs are included in the harness. In this way you can add or remove the Unichip whenever you want. Once removed there will be no footprint or trace of the original installation at all.