High sensitivityWith sensitive semi-conductor sensor, it can accurately and easily show your level of the alcohol in your body within seconds and provide you high accuracy test result(up to 0.01mg/l), four units of measurement can be converted(%BAC , BAC, mg/l, mg/100ml). Automatic Alarm FunctionThe buzzer will automatically alarm when the alcohol content is exceeded. The portable alcohol tester provides you with high-precision test results, always monitoring your alcohol concentration and making more informed decisions about drinking.Resolutely not driving car after drinking. Clear large LCD ScreenNight display and give you professional accuracy for safe driving. Make alcohol testers turn off automatically to save power when you have completed the test for 5 seconds. Easy HandlingEnergy-saving Mode - Easy to use. After loading 3 AAA batteries(NOT Included), turn on the alcohol detector to start the test. Wait 20 seconds for warm-up work, Then use the mouthpiece to blow the tester for 5-6 seconds, and the result will appear in the display. Quick response and accurate result. NoteFor more accurate measurement readings: Please use the Breathalyzer at least 20 minutes after drinking, and then test, you'd better test it last one time that last 3 minutes.due to the absorption of alcohol from the digestive system to the blood takes about 20 minutes. Test it immediately after drinking , the results can only reflect the oral alcohol.Be sure to flash the characters to blow, otherwise do not work.