Features: Ensures your pool or spa is alway in working order with Stack Flue Sensor and Heater Thermistor High Limit Switch set, for seamlesses compatibility with heaters. This comprehensive replacement set includes a stack flue sensor, heater thermistor, and high limit switch, all crafted from materials to accurately monitor and maintain safe heater operations. Suitable for professional pool maintenance personnel and managers who prioritize consistent water temperature and Systems reliability for environment. Whether it's for routine upkeep or emergencys repairs, this kit is essential for maintaining the electrical systems of residential or commercial pools and spas. With easy installation and precise temperature monitoring, the sensor and switch kit not only extends the lifespan of your heater but also ensures a safe, enjoyable swimming experience for all users. Specifications: Texture: Metal Part Number: 42002-0024S 42001-0053S 42001-0063S Working Temperature Range: -20 ℃~80 ℃ Size: As Picture Shows Package Includes: 1 Set Stack Flue Sensor note: Please allow 1-2cm errors due to manual measurement. Due to the differences between different monitors, the picture may not reflect the actual color from the item.