BACtrack Select S-50 Digital Breathalyzer - Grey: The BACtrack Select S-50 is a hand held Breathalyzer that screens for Alcohol. BAC tests provide an estimate using advanced alcohol sensing technology. The S-50 is advanced enough features for Professional use, But it's simple features of operation also makes it simple for personal use. The BAC S-50 comes with replaceable mouth pieces individually wrapped. Attach a mouth piece, press power, and begin testing. The S-50's proprietary Flow Check™ feature ensures that a continuous deep lung air sample. This maximizes reliability and accuracy. Key Features: -There's a wide test range on the BAC, it displays three digit accuracy with very recognizable format from 0.00 to 0.40% BAC. - Proprietary FlowCheck™ feature ensures continuous deep lung air sample - Individually wrapped mouthpieces suitable for both personal and professional use. - Elegant ruby-red LED display - easy to view in low light situations.