Spa Thermostat Mechanical 5/16"x18" Hydroquip 3263-00 Spa Thermostat 5/16"x18" Hydroquip 3263-00 Manf. Invensys Appliance Controls Manf. # 275-3263-00 Thermostats Single pole rated at 25 amps with max temp rating at 107°F. Best results are obtained when the bulb is installed in a dry well or groove tube at or immediately before the heater. This is a safety device! If it is found to be out of calibration, do not attempt to perform a field adjustment! Replace bad thermostat with a new one Capillary Length: 18" Bulb Thickness: 5/16"
