I’m not sure what kind it is, but it’s an expensive one we borrow from a friend who works at a place who sells these to police and others.

The measurements are actually in per mil, which, by Wikipedia, is “a tenth of a percent or one part per thousand.  It is written with the sign ‰.”

So .7% BAC is actually 7‰ per mil BAC.  That means that if someone is measured 2.5‰ BAC, they are actually .25% BAC :)

Thanks for asking and watching, bottoms up!