Good question! A Harvard Law educated Assistant United States Attorney asked me the same thing after I beat her in a DWI/Manslaughter trial a couple years ago ...
PBT = Preliminary Breath Test. Roadside sobriety testing units that aren't usable as evidence of intoxication, but give ya fair warning that you may have had a couple too many.
Ours is known as "County Fair" as it is the centerpiece of the beat the guesser game played at our christmas party, etc ...
