Tips: In order to get more reliable record as possible, advise that you should make the test after least 45 minutes after drinking.Use 2 x 1.5V AAA alkaline batteries (Not included).Operating time:warm up:10s response:<;;5s.Environment temperature:5-40 degreesColor: BlackItem size: 110*70*25mmNet weight: 55gPackage weight: 64gWhen using precautions, must see !1 after drinking , it is recommended to wait 20 minutes before testing, because alcoholtakes about 20 minutes into the blood from the digestive organs , and residual alcohol inthe mouth takes time to dissipate .2 To get a more accurate result , the distance should be at least three minutes betweeneach test .3 Do not use benzene , gasoline and thinners cleaning product ingredients tester .4 Do not allow any liquid penetrated into the sensor.5 to remind you , to you and the safety of others , do not drink and drive.For aviation security reasons, this product delivery without batteryPackage Content:1 x Manual+1 x Digital Breath Alcohol Tester Gun+5 x Breath inhaler CaseThe product will be delivered within 25 days, please rest assured!Welcome to my store, we will be happy to help you, please send me any questions, we will reply you within 24 hours