High Accuracy SensorYou can get the accurate blood alcohol concentration with the upgraded high sensitivity semiconductor sensor in seconds. Certified digital breathalyzer recognized by all kinds of professionals. Instructions are in English. If you need French manual, please contact us. USB Rechargeable and Long LastingCome with USB data cable, the breathalyzer is rechargeable. It is very convenient for you to charge it by USB on your car, computer, socket or power bank. Alcohol test can last for 300 times after fully charged. the device without contact to avoid contamination, the test is more reassuring. And we put everything in a gift box, especially we prepared a portable velvet bag in your car and a perfect gift for your friends. 2 UNIT OF MEASUREMENTThere are 2 units of measurement to choose from, %BAC, g / l. After 3 minutes of testing without a command, it is automatically deactivated. Do not use the breath analyzer until 20 minutes have passed since the last drink consumed. Wait at least 3 minutes to start the next test after the last test. LCD Screen WarningWith LCD screen to see the result clearly and with 3 colors to remind you whether the alcohol test result is safe or not.They are separately green,yellow and red, green means safe, yellow is warning and red is danger. For measurements at or above the alarm concentration level, the analyzer beeps simultaneously. Number of pieces delivered: 1