Let's you monitor the effect that alcohol has on you BAC, one drink @ a time. PRICELESS. Not only would I recommend a BACtrack device, I'd buy a friend one.
My mom passed these out to my sisters and me at a family gathering earlier this year and we thought it was funny but it has honestly been the best gift ever! I use it all the time when I am out and if it says I am close to or over the legal limit then I call a cab and don't worry about if I *think* I am ok to drive and hope I don't get pulled over. Such a thoughtful and useful gift for someone you love. I just got one for my husband as well as the additional mouthpieces because our friends ALWAYS want to use it to to test themselves before they get in the car. I absolutely love this and highly recommend!