Toad ai606 wont detect shocks to the outside by default, you will have to get a 2 stage shock sensor, basically if someone taps your car it gives a pre warn (beeps at them 5 times) if there is a large impact to the car, like someone smacking off the locking wheel nut caps or actually hitting the car it will trigger the full alarm, the interior ultrasonics are very good on the toads also