High precision and digital LCD displayDesigned using a super sensitive semiconductor sensor system our portable breathalyzer,accurately display alcohol content in blood within seconds. Alcohol tester gives you a highly accurate test result, reliably withstands high BAK values. The red background light makes reading easy even at night.Automatic alarm function and energy saving modeIf the result of the measurement exceeds 0.5 BAC, the breathaliser will warn you with an audible alarm. Breathalysers will shut off automatically 5 seconds after the test is completed in order to save power. In addition, it has a battery level indicator.One touch operationThe breathalyser is extremely easy to use. Just insert the two 1.5V AA batteries( NOT included batteries), turn on your breathalyzer, equip the mouthpieces, and then blow directly, clean and hygienic. You can easily change the units of measurement and set custom BAC thresholds for testing.Easy To CarryAlcohol breathalyzer is small and saves space,it also comes with 12 mouthpieces, which can be cleaned and replaced at any time.In addition,It also have a portable bag,can perfectly hold the alcohol tester and mouthpieces.It is very convenient to carry that you can carry it in your pocket or backpack.