MRCOOL NV50-3834 Universal Series 50 FT Pre-Charged Quick Connect Line Set is a refrigerant line set designed to connect compatible indoor and outdoor HVAC units. It works by providing a sealed, pre-charged pathway for refrigerant to circulate efficiently between system components, eliminating the need for vacuuming during installation. Designed for use with compatible MRCOOL Universa... https://www.partshnc.com/mrcool-universal-series-pre-charged-quick-connect-line-set-nv50-3834