Electronic car thermometer with LCD display. It allows you to measure the external and internal temperature through two independent temperature sensors. Powered from the cigarette lighter socket. Manual: Choose a suitable space in the car, away from direct sunlight, air conditioning or heat supply (e.g. dashboard). Wipe and clean the area, remove the protective paper from the adhesive pad on the back of the thermometer. Press firmly in place. Insert one of the batteries included in the package to activate the thermometer and insert the cigarette lighter plug to illuminate the backlight. Battery Replacement: Remove the cover and replace the old battery with a new one of the same type and power. The battery should be replaced when the image on the screen is out of focus. Important: If the units are not working properly, recharge the battery. Sensor Attachment: Remove the protective paper from the sensor cap and press firmly in a place where there is no direct sunlight, rain, wind, mud (e.g. the area behind the front bumper, the front door hinge). Fuse Replacement: Unscrew the plastic cover on the top of the plug and pull out the capsule containing the fuse. Replace the old fuse with a new one of the same wattage. Specifications: power supply: 12/24V Temperature range: Indoor: -20°C to +70°C outdoor: -50°C to +70°C Blue backlight