ARU Thermal Regulator #77707-0010 Compatible with MasterTemp 400, 250, 125, 200, 300, 333 and Sta-Rite Pool Spa Heaters SR200, SR333, SR400

Wide Compatibility: Directly replaces part numbers 77707-0010 and 38000-0007S. Compatible with MasterTemp models 125, 200, 250, 300, 333, 400, and Sta-Rite Pool Spa Heaters models SR200, SR333, SR400.Easy Testing & Diagnosis: If you think the thermal regulator may be faulty, you can test it by placing it in water heated to at least 130°F. If it is working properly, the regulator should open.Simple Installation: It's located between the inlet and outlet water connections on the water manifold. No special tools are needed - replacement takes just minutes.Regulating Temperature: Our thermal regulator ensures your pool or spa heater operates efficiently, providing quick heating and reliable temperature maintenance for optimal comfort.The product includes regulators, springs, valve covers, a clip, and replacement O - rings.