MRCOOL DIY50-1412C-O DIY 18K BTU 1/4 x 1/2 50 ft Mini-Split Line Set is a pre-charged refrigerant line set designed to connect compatible MRCOOL DIY mini-split indoor and outdoor units. It works by providing a sealed pathway for refrigerant to circulate between system components, enabling efficient heat transfer for cooling and heating operation. Designed for use with MRCOOL DIY ductl... https://www.partshnc.com/mrcool-diy50-1412c-o-50-ft-pre-charged-line-set