Replacement control board for pool and spa heaters compatible with the listed models. Designed as a direct electrical system replacement to restore control functions and reliable operation. Key benefits Restores full control board functionality for compatible heaters, eliminating intermittent faults caused by worn or damaged electronics. Durable construction reduces risk of premature failure from heat, moisture, and corrosion. Low electrical impedance reduces energy loss and voltage drop, helping maintain stable circuit operation. Features and performance material quality: Manufactured with substrate materials that provide electrical insulation, strong mechanical integrity, and heat resistance for stable operation in varied environments. Corrosion and oxidation resistance: Surface treatments and material selection extend service life in humid or corrosive conditions typical of pool and spa equipment locations. Low impedance design: Minimizes energy loss during current transmission to support efficient and consistent performance of the heater control circuitry. Strong insulation and isolation: Effectively separates circuit areas to reduce the risk of electrical leakage and short circuits under normal and challenging conditions. Thermal and moisture resistance: Engineered to operate without performance degradation across expected temperature ranges and in humid environments common to pool equipment rooms. Compatibility Compatible with the following control boards and heater electrical systems: MasterTemp 200, 250, 300, 400, 400HD control board StaRite MaxETherm SR200NA, SR333NA, SE400NA, SR200HD, SR333HD, SR400HD control board Compatible with NA and LP series pool and spa heater electrical systems Typical applications Replacement control board during routine heater to restore reliable ignition, monitoring, and control functions. Preventative maintenance upgrade for older heater units showing intermittent faults related to control electronics. Use in service and shops as a stocked replacement part for field service of compatible pool and spa heaters. Installation note Intended as a direct replacement for the listed control boards. Installation by a qualified technician is recommended to ensure correct wiring and safe operation.