Popeye, between you and me< I wouldn't waste your money...my finger, or I should say my thumb was always faster than the foot...it's those officers who leave their units off and only turn it on when they see a speeder that will get you...in the old days when I just left mine on, I was just cruising really not looking to pull anyone over...except the idiot that didn't slow down when he would see me...marked car and all...if just gives you a safe feeling, but if they want you, they will get you...