The MRCOOL DIY25-3858-O is a 3/8 x 5/8 pre-charged quick-connect line set designed for compatible MRCOOL DIY ductless mini-split air conditioning and heat pump systems. It provides the refrigerant pathway between the indoor and outdoor units, allowing refrigerant to circulate efficiently during cooling and heating operation. The pre-charged design helps simplify installation, while qu... https://www.partshnc.com/mrcool-25-ft-pre-charged-quick-connect-line-set-diy25-3858-o