Normally open relayWith sound alarm function2 Units: or Specifications:Temperature control range: -55C-120C or -67F- 248FTemperature control accuracy: 0.1 C or 0.1 FDisplay color: red blueWorking power supply: DC12V DC 24V AC110V-220VSensor: NTC 10K 1 Meter (with probe)Product Size: 79.2mm41.9mm26.3mmHole Size: 72.1mm39.2mmproduct weight: 52g12V or 24V,59g110V-220VOperation display panelPackage included:1 Digital Temperature Controller with Buzzer Alarm1 NTC Sensor1 ManualCode TableP0: Heat or CoolP1: Backlash, 0.1-30 or 0.1-54P2: Set upper limit, -55-120 or -67-248P3: Set lower limit, -55-120 or -67-248P4: Calibration, -10-10 or -27-27P5: Delayed start, 0-10minP6: Alarm temperature, -55-120 or -67-248P7: Temperature unit, or P8: Data lock, ON or OFFHHH: Temperature exceeds alarm temperature (The temperature drops below the alarm temperature returns to normal.)LLL: No temperature sensor detected (Replacement reconnect temperature sensor)12V 24V 110V 220V Digital Temperature Controller Incubator Thermostat Regulator Thermoregulator with Buzzer Alarm and NTC O20 20