Professional Breathalyzer Keychain, Portable Breath Alcohol Tester Red Backlit Breath Analyzer High-Precision Breathalizer with LCD Display, Black

This breathalyzer is very affordable. I have used mine for several days and it still works. It is very good to tell you BAC after one drink, then two, and so on, waiting 20 minutes between each drink to find out your BAC. It is also good to determine your BAC after you have awakened. It is unfortunate that a 0.08 BAC is attained after only one 15 oz. beer and it's the BAC you might wake up at. A 12 oz. beer and your BAC should be around 0.06 if you weigh 250 pounds, which is below the legal limit and apparently 0.08 BAC is the limit at which you can tell you are beginning to be UI but you are still mostly sober. Two 12 oz. beers will put your BAC at 0.12. It is interesting to learn these things with this breathalyzer and it is quite the experience to learn these things with this tool. Discovering that very little alcohol makes ones BAC so high suddenly, but because of this device I now know how little I have to drink to be under the 0.08 BAC legal limit. 2 oz. of 80 proof liquor is a 0.16 BAC at 250 pounds. That's terrible. The only alternative is to not get behind the wheel of a motor vehicle after having any alcohol at all. Even a drop of alcohol will probably register on this breathalyzer, but I dont know that really, it may take a few drops. Read the directions on how to use it.

I have had this for a couple months and unfortunately missed the return window. I have used this no less than 10 times and it has only worked once. It reads 0 BAC every time I use it regardless of how much alcohol I’ve had. Don’t waste your money

This thing is small and it's probably fairly accurate for a breathalyzer of it's size, but that's the problem. I have used this thing a few times but I could never figure out how accurate this is. It appeared to work three times out of five, though not consistently. It was fun while I had it. I think it'll work well as a gag gift.

This is the second breathalyzer I've owned. This one is vastly superior. I've had it two years and it is still fast and accurate.

The directions are somewhat hard to follow but the device itself is very accurate. Also have the very smallKeychain one and that consistently registers too high. Would recommend for someone looking for a small very accurate device.

I'm doing the keto diet. When in ketosis, you breathe out acetone. From my research, I learned that acetone is one of the by products of ethanol (alcohol that we drink). I read that inexpensive breathalyzers work through semiconductors. They cannot tell the difference between ethanol and acetone (police breathalyzers work through platinum, and their machines know the difference). So I bought this. I blew at a SLOW and CONSTANT rate into the machine for as long as possible (the acetone fumes come at the end of the breath). It measured acetone level of 1.1. I then compared this to a urine ketone strip. It's measurement was 1.5 to 2. I'm satisfied that I have what I wanted.

Does not work

This worked sometimes. I followed all instructions and when i blew into it after having my last drink 30 min ago it said I was over the limit. After one drink. it can read hard liquor but not wine.