1. HIGH ACCURACY: Alcohol detector uses high accuracy semiconductor alcohol sensors to monitor your blood alcohol content to 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 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 be displayed on the LCD screen for 5 seconds. 4. MEASURING RANGE: Alcohol measurement range is 0.00 to 0.19% BAC and 0.00 to 0.99mg/l, and the alcohol test result reaches the maximum value (0.19% BAC), which not increase. Even with an increase in alcohol consumption, the test results still showed 0.19% BAC. 5. AUTOMATIC SHUTDOWN: In any state, you can and hold the button for 0.5 seconds to directly shut down, or the tester automatically shut down after displaying the test results. Specification: Item Type: Breath Alcohol Tester Charging Voltage: DC 5C Power Supply Battery: Lithium ion battery 140mAh (built in carrying) Test Range: 0.00 to 0.19% BAC and 0.00 to 0.99mg/l How to Use: 1. Twist the dust cover to the left. 2. and hold the power button for 0.5 seconds, and the display screen after the "beep" sound. 3. Display "preheating" to preheating for 10 seconds, and the number starts counting down from 10 to 00. 4. At of the countdown, after the sound of "Didi Di", the countdown from 06 to 00 when "Blowing" is displayed. Blow in at any time during this countdown, and stop blowing after a beep. 5. Read the test results from the display screen of the tester. 6. In any state, you can and hold the button for 0.5 seconds to directly shut down, or it automatically shut down after displaying the test results. 7. To obtain more accurate results, please take the average of 3 tests every 2 to 3 minutes. Color: Black Material: ABS Package Contents: 1 x Portable Handheld Breathalyser Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.