Thermostat, AC Control, RED DOT - ELE-010-198

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Thermostat, AC Control, RED DOT - A/C (Electric) Control Thermostat - 198 Degree
This thermostat is used on 431 series of Aqua-Hot, which includes 920-431/12, AHE-100-00S, AHE-100-01S, AHE-100-02S and similar. Includes new mounting and terminal screws.
Looks like this: