High quality pure copper fittings and flare nut Includes 2 flare nuts, a pair of connectors and direct purchase copper tubing as needed Uses: The connection between two copper pipes, one to two, quick connection, no soldering, can be tightened with a wrench. Air Conditioning Copper Pipe Joints 6-19mm Double Joint Intermediate Joints Copper Core 6-19mm top quality Sturdy and durable Not easily damaged during installation. The joint is used to lengthen the copper tube, it can be used when purchasing, no soldering is required. Attention: the copper tube for air conditioning contains double tubes of different sizes. You need to purchase the corresponding 2 pairs of connectors according to the size of the air conditioner.