This Digital Breath Alcohol Tester LCD Display with Audible Alert Keychain has compact and lightweight design for measuring BAC. With it， you can use a simple method to analysis blood alcohol concentration at anytime and anywhere， bring you more convenient in life!                                    Features            With audible alertQuick response and resumeAuto power offUse mouthpieceKey chainDigital LCD display                                                            Specifications            Sensor    Advanced semiconductor oxide alcohol sensor    <br>Range    0.00-0.19% BAC !#!amp!*! 0.0-1.9g/I    <br>Power Supply    2 x 1.5V "AAA" alkaline battery    <br>Operating Time    Warm up: 10s; response: !#!lt!*! 5s    <br>Dimension    2.0" x 1.1" x 4.5" (L x W x H)    <br>                                                            Package Includes            1 x Digital Breath Alcohol Tester LCD Display with Audible Alert Keychain4 x Mouthpiece1 x User′s Manual                                                            Extra Info            NULL