AC insulated copper tube, it is used for install the Air conditioner, it connect the indoor unit and outdoor unit. About the structure, the inside is copper tube, outside is covered with NBR insulation tube. The out insulation tube have two types, white and black NBR tube. AC insulated copper tube usually have 3Meter and 5 meters, with flare nut. And also have 20meters and 30 meters, when the customer got it, can cut at any meters they need.