Fangrui Product Details Description: Portable And Durable, Easy To Carry, Lightweight Exhale Air Alcohol Content Tester Is Professional Device Testing Alcohol Of Human Exhaling Air Alcohol, The Sensor Is Hanwei Electronic Advanced Namo Semi-conduct Alcohol Sensors, It's Good Sensitivity And Excellent Repeating Function; Testing Program Is Controlled By Artificial Intelligence Design Micro-computer Controlling, Working Process Is Reasonable, Simple And Portable, Full Functions, It's Many Kinds Of Applicable Capabilities;backlight Lcd Digital Character Photo Displaying, Clear And Straight; Small And Portable Design Is Convenient To Use.when Tested Exhaling Air Alcohol Content Is Over Preset Value, The Device Will Sound Alarming Signal, Reminding Your Safety. Advanced Flat Surfaced Alcohol Sensor Quick Response Smd Assembling, Stable Performance Direct Testing Process Lcd Indication Digital Lcd Display With Blue Backlight Portable And Fashion Design Audible Warning Beyond Preset Limit Sensor Fault Self Checking Battery Saved Design,low Voltage Indication Digital Lcd Display Specifications: Sensor Type: Nano Semi-conduct Alcohol Sensor Working Power: Dc4.5v( 3 X Aaa Battery) Undervoltage Display: Vcc Crafted With Attention To Detail