The branch pipe is also called air-conditioning branch or Copper Refnet Joint, Y branch pipe, etc. It is a connecting pipe used in VRV air-conditioning system to connect the host and multiple terminal equipment (evaporators), and is divided into air pipe and liquid pipe. The trachea is generally thicker than the liquid pipe. The refrigerant passes through the expansion valve or capillary throttling, and then comes out of the main engine outlet and then connects to the liquid pipe of the branch. The refrigerant can be divided into other branch pipes and end evaporators by branching through the liquid pipe. After the refrigerant absorbs heat into gas in the evaporator, it flows back to the compressor of the main engine through the gas pipe.It's mostly made of Copper TP2 and will have the different diameter based on different brand's air conditioner.