Fast and Accurate Alcohol Tester: The alcohol tester uses a high-precision semiconductor alcohol sensor to provide fast results in just 5 seconds, with accurate feedback on alcohol content, without the need for a disposable mouthpieceEasy to Use: The breathalyzer is simple to use and everyone can easily perform a blood alcohol test. Simply turn on the alcohol tester and blow for 5 seconds, and your BAC result will be displayed with clear, easy-to-understand feedbackPortable and Easy to Carry: Our keychain alcohol tester has a compact and lightweight design and is equipped with USB-C fast charging function, ensuring that your personal alcohol tester is always available and can be widely used to test friends at bars and test family members at home gatheringsColor differentiation of sound warnings: This alcohol tester is designed for responsible drinkers who want to stay safe. When the test result is greater than 0.05% BAC, the screen will turn red and a continuous sound alarm will sound to remind you.Portable and Compact: The pocket alcohol tester is placed on the keychain and can be carried with you, which is perfect for checking alcohol content at weddings, parties, banquets, or after drinking in the bar