A slam lock is a device that automatically locks the vehicle door immediately when it is shut, without requiring any operation by the driver. Human error is the single largest cause for vehicles being left unlocked. It will automatically lock when the vehicle door closes and cannot be reopened unless the correct high-security key is used, ensuring the door is always locked which dramatically reduces the chance of theft from the vehicle.

It is primarily designed for applications such as multi drop delivery, high value loads and applications where the owner/ operator requires control over the security of their goods. It is the function that appeals as much as the security. Another major advantage with mechanical slam locks is total control.