The MRCOOL MHK20P Signature Series Heat Kit is an electric heating accessory designed to provide supplemental or emergency heat for compatible MRCOOL Signature Series air handlers. It works by converting electrical energy into heat, which is distributed through the air handler to maintain comfortable indoor temperatures during cold weather or when additional heating is required. Commo... https://www.partshnc.com/mrcoolr-signature-series-heat-kit-mhk20p