MRCOOL DIY-18-HP-WM-230C25 DIY 4th Gen Energy Star 18K BTU Ductless Mini-Split Heat Pump System is a complete heating and cooling solution designed for residential spaces without ductwork. It works by transferring heat between the indoor and outdoor units using advanced heat pump technology to provide efficient cooling in summer and dependable heating in winter. https://www.partshnc.com/mrcool-diy-4th-gen-e-star-18k-btu-ductless-mini-split-heat-pump-diy-18-hp-wm-230c25