Do I need a breathalyzer. For some areas and professional, this may make sense, if you even want to be absolutely on the safe side. Apart from that everyone is his own fortune. For me personally, apply behind the wheel of an absolute 0.00 blood alcohol limit. But this is not the place for ideological debate. This breathalyzer helps whenever time ever times want to know what the levels after two to three glasses says so. The handling is very simple and self-explanatory for faster reading of the manual: Switch on the instrument, blow long enough and read the value. My feeling (unfortunately I do not have a comparison device), the alcohol content meter operates pretty much. The device itself is very compact and handy and can be taken anywhere. A mouthpiece for personal use is integrated, five more settled. In addition, the sensor can be replaced independently, so that the device always works exactly. Conclusion: A useful device that has already taken care of in good company for one or the other eye-opening moment.