MRCOOL MHK05P Signature Series 5 kW Packaged Unit Heat Kit is an electric heating accessory designed to provide supplemental or emergency heat for compatible packaged HVAC systems. It works by using electric resistance heating elements to generate warm air, which is then distributed through the packaged unit's blower and ductwork. https://www.partshnc.com/mrcoolr-signature-series-heat-kit-mhk05p