Its this model $80 shipped
http://www.gtechprostore.com/cgi-bin...ion&key=010100

comes with the manual. All you have to do is plug it into your cigarette lighter, and plug in your car's weight and its good to go.

It can measure your
0-60 times
60-0 braking distance
1/4 mile E.T.
1/4 mile trap speed
horsepower
Instantaneous Gs
Continuous Gs