W637 Digital Breath Alcohol Tester Easy Use Breathalyzer Alcohol Meter Analyzer Detector with LCD Display <ul class=productAttributesList><li><span>With LCD Screen Or Not:<span><span>Yes<span><li><li><span>Gas Type:<span><span>Alcohol<span><li><li><span> Resolution ratio: :<span><span>0.1<span><li><li><span> Reaction time: :<span><span>1 (s)<span><li><li><span> Power supply: :<span><span>2 x AAA battery(Not Included)<span><li><li><span> Weight: :<span><span>70 g<span><li><li><span> Support::<span><span>Dropship<span><li><ul><div>Features: 1. Detection range:0.000% - 0.199% BAC 0.000-0.995 mgl 2. Digital display results (% BAC mg l) 3. Quick response and recovery. 4. Automatic power outage. 5. Orange back-light. 6. Low voltage indicator. Specifications: 1. Resolution ratio: 0.1 2. Reaction time: 1 (s) 3. Power supply: 2 x AAA battery(Not Included) 4. Weight: 70g Instructions: 1. Press the switch once, the LCD screen of the tester will turn on the lights, and it will send out a "noise". 2. The state of warm up number will jump from 10 to 0, and after the state blow 10 jumps to 0, the preheating program will be completed. 3. When the countdown is 6 seconds, the mouth is close to the breath test sensor and exhaled for 3-5 seconds to the sensor. 4. The screen can read the test results.<div>