Motor insurance repair research centre Thatcham has revealed the first companies to be awarded category five accreditation for their vehicle tracking systems.

Some insurers require Thatcham-approved security systems be fitted as a condition of cover on certain cars. Others offer discounts.

The organisation gave the green light to products made by Cobra Vehicle Security, Matrix Telematics, National Communications Group, Richmond Design & Marketing, Scorpion Vehicle Security, Tag Guard, Tracker Network and Trakma8.

A spokesman for Thatcham said: "This list represents about 50% of companies and products on the market. We will be trying to get the remaining companies on board over the next few months."

Category five accreditation is for vehicle recovery systems covering design, installation and maintenance through to operation, tracking and vehicle recovery.