Two High Performance SI (Scientific Image) Cameras determine the geometry via the targets mounted on each wheel. This type of system removes the risk associated with expensive ‘heads’ being mounted on the vehicle, and in our experience the 3D method is particularly loved by tyre shops who are looking for a speedy throughput without compromising on the quality of data provided. In fact, there is a 2 wheel only mode which allows for a ‘fast check’ to get the steering wheel straight and front wheels aligned.