The MRCOOL MHK15B Signature Series Modular Blower Heat Kit with Circuit Breaker is an electric heating accessory designed for compatible MRCOOL modular blower and air handler systems. It uses electric resistance elements to generate supplemental heat, helping maintain indoor comfort when heating demand increases. The integrated circuit breaker provides overcurrent protection for the h... https://www.partshnc.com/mrcool-signature-heat-kit-mhk15b