The MRCOOL MHK05U Heat Kit Universal R-454B Air Handler Heat Strip with Circuit Breaker 5kW is an electric heating accessory designed for compatible MRCOOL R-454B air handler systems. It works by utilizing electric resistance heating elements to generate supplemental heat, which is distributed through the HVAC system to maintain indoor comfort during colder conditions. The integrated ... https://www.partshnc.com/mrcool-5kw-universal-heat-kit-mhk05u