Test Yourself, Friends and Family.One-button Operation – press power and begin testing. Results displayed in less than 20 seconds.Advanced features include continuous temperature checking and internal pump system for breath capture.Crisp 4 digit LCD display provides easy, accurate results, test results in extended accuracy format.Portable breathalyzer is easy to carry.NOTE:Do not use these cleansers such as benzene, thinner or petrol to clean the product to avoid damaging its surface.Do not fall it down or strike, otherwise malfunction may be caused.Do not try to repair, rebuild or dismantle any parts except for the battery replacement.When not use the device for a long time, you are recommended to take out the batteries to prevent the damage due to battery leakage.Specification1 . Voltage: 3V2. Preheat Time: 20s3. Weight: 34g4. Size:4.4 x 2.4 x1.2 inches5. Color: Black6. Power Supply: 2 AAA Battery (not included)7.Range: 0.00-0.19% BAC &0.0-1.9 g/l.How to use the alcohol tester?Wram up1.Press and hold the power button for 1 second, the alcohol tester LCD will turn on with one beep sound.2.The "warm up" symbol is displayed, and the 10 to 00 countdown is started that indicate the tester is in warm-up mode.