PRECISE: Tired of cheap Chinese devices that only give halfway stable results for a short time? The ACE A measures accurately over a long period of time - thanks to a precise electrochemical sensor! EASY TO USE: This breathalyser can be switched on and off with just one button and display the total number of tests performed. The breath test only takes a few seconds INCLUDED IN DELIVERY: With each purchase, you will receive the ACE A electrochemical promille tester as well as three matching AAA batteries, three mouthpieces and a multilingual manual (including German and English)! PRE-CALIBRATED: Our digital breathalyser is shipped calibrated for 1 year with a maximum deviation of only 0.05 parts per thousand. For continued accuracy, we recommend regular calibration. DIGITAL DISPLAY: The display of the measured test results is both in per mille (as is common in the vernacular) and in mg/L (as is common with the police) as well as in %BAC (blood alcohol concentration)!