Display Color: redDisplay Way: 0.28 inch LED digital tube Display: DigitalRefresh Rate: 4s/ Unit : 1PcMeasurement Precision: 1 celsius Operating Temperature: -40~85 celsiusShell Size: 47.8*28.8*15mmSensor Type: NTC metal waterproof probe Power Supply Voltage: DC 4-28VMinimum Resolution: 0.1 celsius Measurement Temperature: -20~100 celsiusColor: BlackMaterial: ABSnstructions for use:[1] DC power supply: This product requires access 4-28V DC power supply, the for positive power supply, the black wire to the negative power. The greatest feature of this product: own reverse anti-burning circuit, avoiding the process due to improper operation problems. Friendly reminder: must not be connected with AC 220V Oh![2] Display When the temperature sensor is removed when the digital display "- - -", the temperature is -20 Celsius or above 100 Celsius , digital also shows "- - -."[3] Acquisition normal temperature range: -20 Celsius to 100 Celsius , resolution 0.1 Celsius , accuracy of 1 Celsius .Product Usage:measuring the temperature inside and outside the carmeasuring the temperature inside and outside the air-conditioned roommeasuring the temperature inside and outside the refrigeratortemperature measurement pondbaby bath water temperature measurementPackage contents:1x monitor2x 1M NTC waterproof metal probe1x Wiring