https://www.thekeylab.co.uk/van-security/
Is a Van Hook Lock Worth the Investment? A van hook lock is an effective method of increasing the security of your van. It is attached to an opening or connecting panel they work independently of the manufacturer's locking mechanism and can only be operated with a key under full control of the driver. As opposed to straight bolt deadlocks, they lock using a hook-style bolt that is inserted into a receiver keep, offering premium vehicle security. High-Security Locks As the world becomes more crowded and hostile, security is one of the most impor