For W1209 board (LxWxH): 48mm x 40mm x 14mm (.9" x. 6" x 0.6"). Refresh rate: 0.5 seconds. The onboard relay can switch a maximum current of 14V DC 20A, 24V DC 16A or 125V AC 7A. Short press the "SET" button, then press the "+" and "-" buttons to increase or decrease the temperature setpoint.
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