The MRCOOL UHK05 Universal R-454B Air Handler Supplemental Heat Kit is an electric heating accessory designed for compatible MRCOOL Universal air handlers. It uses integrated electric heating elements to provide supplemental heat when additional capacity is required during colder conditions. Designed for use with compatible R-454B heat pump systems, the kit supports reliable indoor te... https://www.partshnc.com/mrcool-5kw-universal-heat-kit-uhk05