I received the Homasy Portable Keychain mini breathalyzer free in exchange for my unbiased honest opinion. I think this is quite cute. It would be great for that parent with teens that are suspected of drinking while out or for those that go to the night clubs and want to be sure they are not over intoxicated. It uses a single AAA battery and is small enough to carry everywhere you go. It came with a supply of extra mouth nipples that are placed over the mouthpiece for those people that are germ a phobes and worried they could catch something from using this after someone else but I don’t see a need for them if you are buying this for personal use. It seems to be accurate and is fairly quick. it takes about 15 seconds for the whole process. This helps eliminate the thoughts of being safe to drive with the fact of it being safe for you to drive.