Feature:1. HIGH ACCURACY: Alcohol detector uses high accuracy semiconductor alcohol sensors to monitor your blood alcohol content to ensure that you can drive responsibly.2. NOTE: For more accurate test results, please stop drinking for 20 minutes before using an alcohol tester. The interval between each test should be kept at 2 to 3 minutes.3. EASY TO USE: Turn on the power button of the alcohol tester, wait for 10 seconds to preheat, and then blow evenly for 3 to 5 seconds. The results will be displayed on the LCD screen for 5 seconds.4. MEASURING RANGE: Alcohol measurement range is 0.00 to 0.19 percent BAC and 0.00 to 0.99mg or l, and the alcohol test result reaches the maximum value (0.19 percent BAC), which will not increase. Even with an increase in alcohol consumption, the test results still showed 0.19 percent BAC.5. AUTOMATIC SHUTDOWN: In any state, you can press and hold the button for 0.5 seconds to directly shut down, or the tester will automatically shut down 30 seconds after displaying the test results.Specification:Item Type: Breath Alcohol TesterMode: TS 21Material: PCCharging Voltage: DC 5CPower Supply Battery: Lithium ion battery 140mAh (built in carrying) Test Range: 0.00 to 0.19 percent BAC and 0.00 to 0.99mg or l.Package List:1 x Breath Alcohol Tester1 x Charging Cable (Color Random)1 x Manual