Description: Quickly estimate your blood alcohol concentration with this small and contactless alcohol breathalyzer. No need to worry about forget to install a mouthpiece or hygiene issue, you can directly blow to the tester inhaler without a mouthpiece, more convenient and safe. Portable to carry it with you, testing your BAC at any time and anywhere. How to Use: 1. Press and hold the power button for 1 second, the alcohol tester LCD with turn on with one beep sound. 2. Warm-up mode countdown for 10 seconds. 3. Testing mode countdown from 10 to 00 after warm-up mode, blow at this period. 4. Blow into the breath inhaler for 3-5 seconds with normal power after a deep inhalation. 5. Read the test result from the alcohol tester LCD. 6. Test range: 0.00%-0.19% BAC & 0.0-1.9 g/L Notes: 1. The first use of the tester or after a long time no use, press the power button and retry several times if possible. 2. Repeatedly 2 or 3 times to obtain more accurate results. 3. Do not smoke and eat for 20 minutes prior to testing. 4. The test result is for reference only. 5.Rechargeable with USB cable