This is the OEM bed divider that is compatible with the 5'7" or 6'4" bed trucks with the Rambox style beds. You can place it into the side slots that run inside the bed while it is folded to divide up the cargo space, or attach it to the connectors at the tailgate edge of the bed to extend the cargo area with the tailgate down.
It has a keyed lock and is unlocked so you can always open and close it - but I no longer have the original key. If you wish to match the lock to your truck keys you can have the keyed tumbler easily swapped by your local locksmith or dealership.
As I no longer have my Rambox truck this is just taking up space here so I am listing it for sale.