I don't know how strong is the law here for you, but I live in France, in the country of wine and strict police.
After a party or just a dinner with friends, this alcohol tester is very handy !
It's very easy to use :
- put batteries in it
- press ON
- wait 10 secs
- blow in it
- it will immediately give you the number of mg / L of blood
Of course, you can reuse it as many time as you wish because it's fully digital.
Warning : this device must not be use to build an alcohol contest between friends...