PORTABLE AND COMPACTThe lightweight breathalyzer fits easily in your car, purse, backpack or briefcase, saving space and ideal for weddings, parties, banquets or other social events to ensure you drive safely after drinking. Simply insert 3 AAA batteries (batteries not included) and turn on the breathalyzer.Fast and AccurateThe electronic breathalyzer uses a sensitive semiconductor sensor. After 10 seconds of preheating, simply blow for 3 to 5 seconds to get an accurate reading; the BAC results will be displayed on the breath analyzer's LCD screen on a bright screen. Remember to wait 20 minutes after drinking to get more accurate results.Versatile useElectronic breathalyzer with 20 interchangeable mouthpieces, washable and reusable, suitable for various occasions such as individual use, family gatherings, parties and social events. Conduct three consecutive tests and take the average to ensure accuracy. If you have any questions about the disposable breathalyzer, please feel free to contact us.Measuring RangeThe measuring range of the professional breathalyzer is from 0.000 to 0.200% BAC. Even with increased alcohol consumption, once the breathalyzer result reaches its maximum value (1900% BAC), it will continue to show 1900% BAC. In the test result mode, there are 4 selectable measurement dimensions and by holding down the M button, you can change the units (mg/100ml, %BAC, g/1, mg/l BrAC).Note: Be sure to read the instruction manual carefully before use, if you have any questions, please contact us, we provide 5 years customer service!Built-in Smart AlarmWhen the test result exceeds 0.2 BAC or 0.1 mg/L, the breathalyzer will give voice prompts for drunk driving or drunk driving. This system will immediately warn you when your blood alcohol level exceeds the legal limit, allowing you to drive safely and avoid fines and accidents.