LCD Screen High-Precision Air-Blowing Dual-Purpose Alcohol Tester 1. Detection method: semiconductor gas sensor 2. Breath alcohol concentration measurement range: 0-200mg100mL 3. Voltage: 4.5V 4. Current: 120mA 5. Battery: 3 AA batteries (batteries are not included in delivery) 6. Operating temperature range: -5 to 45 degrees Celsius 7. Storage temperature range: -20 to 50 degrees Celsius 8. Product size: about 135 x 64 x 24.5mm 9. Product weight: about 68g How to use: 1. When using for the first time, please prepare 3 AA dry batteries, remove the battery cover, and install the battery cover before use. 2. Press the power button. 3. "Preheat" for 1-10 seconds, and enter the preheating countdown for 10 seconds after turning on. Please wait for the preheating time. 4. After the preheating is completed, it will automatically enter the blow test countdown for 10 seconds. Wait for the test results to be displayed. 5. Set the display unit: After completing the operation in 2.3.4., within 15 seconds after the display result appears, double-click the button to switch to the next measurement display unit. Note: When the alcohol tester is taken out of the package for the first time or has not been used for a long time, a large amount of gas and other impurities will adhere to the sensor. In this case, you need to press the power button several times to clean the alcohol tester by preheating.