Optima AGM Start-Stop Battery

Stop-start killed the ordinary flooded battery. An AGM or EFB battery is built to be discharged and recharged constantly rather than sitting full, and fitting a standard battery in its place fails within months. Most of these cars also need the new battery registered to the charging system.

Supplied by Optima.

In the box: The battery.

Calibration required. This part must be calibrated to the vehicle after fitting. Without it the system does not fail safely — it reports confident, wrong readings.