A. If you are installing a Chinese-made diesel heater, this three-way connector is suitable for connecting to your diesel tank without removing the tank or drilling holes in it. B. This snap-on three-way connector can be connected to the return fuel line to deliver fuel to your diesel heater. The installation takes about 10 seconds, which is an easy way to connect the heater to the tank. C. Please refer to the last photo to determine the installation position. You only need to press the red button, squeeze and pull out the existing fuel line. Then snap this three-way connector into the existing fuel line and reconnect it. D. It can achieve an easy and convenient connection of the auxiliary heater's fuel pipeline. E. There is no need to modify the vehicle. Just install it between the existing connectors of the fuel return line. F. Scope of application: - It is suitable for Chinese-made diesel heaters. - It is suitable for Vauxhall Vivaro, Renault Trafic, or Nissan Primastar models from 2001 - 2014, and may be suitable for other vehicles. G. Package contents: - 1 fuel return line connector/three-way connector.