MRCOOL DIY35-3858C-O DIY 5th Gen 24K & 36K BTU Line Set is a refrigerant connection kit designed to link compatible indoor and outdoor ductless HVAC units. It works by providing a sealed pathway for refrigerant to circulate between the indoor air handler and outdoor condenser, supporting efficient heat transfer and system operation. Designed for use with compatible MRCOOL DIY 5th Gene... https://www.partshnc.com/mrcool-diy-5th-gen-35ft-3-8-x-5-8-line-set-r-454b-diy35-3858c-o