The MRCOOL MC25-1438 9K & 12K BTU Flared Line Set Kit is an HVAC installation accessory designed to provide a secure refrigerant connection between compatible MRCOOL mini-split indoor and outdoor units. It works by using insulated copper tubing with factory-flared ends to ensure efficient refrigerant flow and reliable, leak-resistant performance. Commonly used with 9,000 and 12,000 BT... https://www.partshnc.com/mrcool-25ft-1-4-x-3-8-flared-line-set-kit-mc25-1438