Breathalyzer, [Professional-Grade Accuracy] Fuel Cell Sensor Digital Breath Alcohol Tester for Personal & Professional Use

After using according to instructions it reports no alcohol in system even though I had several drink prior to testing. I checked every 20 minutes after the drink for two hours. The only rest that reported as immediately after drinking.no of the others reported any level

I bought the unit here about a year and a half ago.and have used it a couple of dozen times. It seems very accurate and is portable enough to fit in a pocket or whatever. It came with 5 mouth pieces. Unfortunately, I have lost 4 of the mouth pieces and it’s impossible to find replacements. If I lose the last one, I’m out of luck. Therefore, I can’t give it 5 stars.