Features: [Accurate Testing ]: The breathalyzer uses an ultra-precision semiconductor gas sensor to accurately feedback your actual situation on the LCD display.Unlike traditional mouth contact testing,our non-contact blow-out test eliminates the need for frequent replacement of the breath tester for suction cleaning and avoids cross-infection.Preheat for 10 seconds and finish blowing. [Simple operation]: Long press the power button for 2 seconds, after the 10-second preheating time is completed, please blow from the front to the mouthpiece at 2-3cm away from the mouthpiece and stop blowing after more than 3 seconds (do not touch orinclude blowing in the mouth).Wait a few seconds to display and voice broadcast the measurement results. [Three-color indicator high-precision breath alcohol tester]: Drunk driving: refers to the driving behavior of the driver of a vehicle with a blood alcohol content ≥0.02% BAC and a blood alcohol content <0.08% BAC. The yellow light was on and the alarm sounded quickly. Drunk driving: refers to the driving behavior of the driver of a vehicle with a blood alcohol content ≥0.08% BAC. The red light was on and the alarm went off quickly. Specifications: Product name: Breathing alcohol detector Battery: built-in lithium battery (200mAH) Charging input: 5V1A Operating voltage: 3.7V Sensor type: semiconductor gas sensor Measurement range of alcohol concentration: 0~200mg/100ML. Net weight: 23g Size: 9.3 * 2.5 * 2.4cm. Indicator lights: red light (drunk driving), yellow light (drunk driving), green light (not drinking) Product accessories: 1* Alcohol tester 1* Charging Cable 1* User Manual