Fast and High-precision Sensor: Features a professional airway design and high-precision semiconductor sensor to quickly and accurately display blood alcohol levels. Helps users make informed decisions regarding alcohol consumption and driving. Easy to Use: Insert 2 AAA batteries and turn on the breathalyzer. Wait 10 seconds for warm-up, then blow steadily for 35 seconds. Results are displayed on the LCD screen. The device automatically powers off when not in use to conserve energy. (Batteries not included) High-Quality Breathalyzer: Utilizes advanced solid-state alcohol sensor technology to rapidly analyze breath samples and estimate blood alcohol concentration (BAC). Automatic Warning Function: Displays a warning when results are between 0.02% and 0.05%, and indicates danger when results are 0.05% or higher. For most accurate readings, wait 20 minutes after drinking before testing.