Group 1 provides the very best standard of stability with equally alarm and immobiliser features put together. Class 2 offers only an immobiliser, which nonetheless stops the vehicle from commencing without authorisation. Each are passively set and provide outstanding protection against theft. Thatcham is renowned not only for stability tests https://medium.com/@trackerfit11/why-choosing-a-thatcham-tracker-strengthens-vehicle-security-6b79d8a9c256