This alcohol tester is very handy for measuring the blood alcohol content in yourself. The alcohol test operates on two AAA batteries (not included) and requires ten seconds to warm up. Once the test has warmed up, blow into the top of the inhaler for 3 to 5 seconds, and the result will appear on the LCD screen. The alcohol percentage is displayed in the values Caution: 0.02% and Danger 0.05%. You will get the most reliable result if you repeat the test 2 to 3 times. With this alcohol breath test, you not only save on fines, but it can also save your own or someone else’s life.