Features: The blue back light makes it easy to see the results at night, whether you're indoors or out, and shows how drunk you are. Portable breathalyzer is with a simple and convenient design for analyzing blood alcohol concentration any times and anywhere. This alcohol tester has a high-precision semiconductor alcohol sensor. It can quickly provide a result to judge whether you drive or not. Automatic shutdownand energy saving function, the mouthpiece can be replaced by a total of 12 mouthpieces. It is very suitable for weddings, parties, celebrations and other social event to help you assess whether it is suitable for driving. Specifications: Material: plastic Size: approx 10.92x5.08cm/4.3x2inch Sensor: semiconductor alcohol sensor Power consumption: 2x1.5V AAA batteries (not included) Response time: <5s Warmuptime: <10s Auto shutdown: approx10s Package Includes: 1xAlcohol Tester note: Please allow 1 to 3cm error due to manual measurement, please make sure you do not mind before you bid, Due to the difference between different monitors, the picture may not reflect the actual color of the item.