Class 1 features the best standard of stability with both equally alarm and immobiliser features mixed. Group 2 offers only an immobiliser, which still stops the car from commencing without the need of authorisation. The two are passively established and supply fantastic protection towards theft. S5 trackers (previously referred to https://medium.com/@trackerfit11/why-choosing-a-thatcham-tracker-strengthens-vehicle-security-6b79d8a9c256