This product is a alcohol tester it is small exquisite and delicate design it is so easy to carry! LCD digital which can make detection more efficient. With voice alarm function when a alcohol content is excess the buzzer will alarm automatically alert. No need to use blowpipe just blow into air hole this way is healthy and clean. - Measures 0.00~0.19% BAC 0.0~1.9g/l - Displays exact readings and advices on screen - Fully digital alcohol tester - Quick within the second response - Auto power off - Alarm Clock feature - Count down timer (for parking) - Clock powered by 1x AG13 battery (included) - Alcohol tester powered by 2x AAA batteries (sold separately)