This model has an LCD screen which shows the concentration level of CO from 0 to ***0 ppm. The screen has a LED lighting so you can see the concentration of CO even in complete darkness. The SITERWELL Carbon Monoxide Detector is powered by 9V batteries. This allows you to use the detector everywhere – in the car, in the office, in the caravan and so on, because he does not need to be powered by electricity. When the appliance is in Standby mode, it has an extremely low consumption of energy <*0mA. When the battery is low, the green indicator starts blinking continuously and it is displayed on the LCD the Lb symbol (Lb – low battery). If the concentration of Carbon Monoxide exceeds *0 ppm, the red indicator starts blinking. If the room is not ventilated within *0 minutes, the sound signal is enabled. The appliance has a method for testing the function of an Electrochemical Sensor and an Error message is displayed in case of damage.