High-precision digital breath analyzer With advanced semi-conductor sensor ensures accurate readout in short time.When using alcohol tester for the first time or hasnt been used for a long time, press the power button a few more times to clear the semi-conductor sensor internal excess gas to ensure accurate readings. High sensitivity Make alcohol testers turn off automatically to save power when you have completed the test for 5 seconds.Please test after drinking for at least 20 minutes because it takes about 20 minutes for the alcohol to be absorbed from the digestive into the bloodstream. If testing immediately, it can only reflect the alcohol concentration in the oral cavity, not in the blood. With backlight LCD displayMake it much easier for the night display and give you professional accuracy for safe driving. Easy Handling Breathalyzer just one-button operation, it's easy to turn the device on and test it in seconds. Portable alcohol breathalyzer Space saving, lightweight, completely easy to hold and carry everywhere.For more accurate measurement readings: Do NOT smoke or eat within 20 minutes before testing. The test time should be after 3 minutes from the last test. Packing:1xBreathalyzer