Portable breathalyzer is designed to help you drive safely after drinking in a business negotiation, family gathering, party, dating or more situations. It adopts sensitive semiconductor alcohol sensor which brings quick and accurate results. Better repeat testing for 2-3 times and DO NOT drive if it shows "Caution" or "Danger". Backlit LED digital display, clear at a glance. Caution: 0.02% BAC (0.2-0.5g/L); Danger: ≥0.05% BAC (0.5g/L), with sound alarm Adopts semiconductor alcohol sensor, easy operation, quick and accurate result. Better repeat testing for 2-3 times 5 mouthpieces in total can be easily replaced; rotate to install or remove Battery operated, auto shutdown after about 10s idle time to save energy Compact and lightweight, portable to carry in pocket, backpack, laptop bag, car and so on Specifications: Material: ABS Sensor: Semiconductor Alcohol Sensor Accuracy: -0.01~0.02% BAC (0.05% BAC Alarm Value) Preheat Time: 10s Blow Time: within 10s (Better for 3-5s) Power Supply: 2 * AAA Battery (Not Included) Auto Shutdown: about 10s Item Size: Approx. 11 * 3 * 7cm / 4.33 * 1.18 * 2.76in Item Weight: Approx. 40g / 1.41oz