NON CONTACT DETECTOR: Designed with gas receiving holes, 4 seconds non‑contact blowing detection. Save money and be healthy.Built‑in imported high‑ sensor chip, detection accuracy of ±0.01% BAC, detection range of 0.00‑0.19% BAC (0‑1.9G/L).Test range: 0.00%‑0.19% BAC & 0.0‑1.9g/L. PORTABLE DESIGN: Small and portable, the alcohol tester can be placed on the car console and ready to use. Good for travel.From personal, parental, to banquet, bar or professional use, a quick, easy and reliable way to test their alcohol . HOW TO USE: 1. Press and hold for 1 second, the alcohol tester LCD will beep and turn on.2. The preheat mode counts down for 10 seconds.3. The test mode counts down from 10 to 00. After the preheating mode is over, blow this time.4. After a deep inhalation, blow with normal power for 3‑5 seconds. 5. Read the test results from the alcohol tester LCD DISPLAY. ACCURATE ALARM MODE: