What is required for prisoners to carry while in installation custody?

The requirement for prisoners to carry a DD Form 512, which is a "Prisoner Transfer Document," is essential for documentation and tracking purposes while they are in installation custody. This form serves as an official record that outlines the specific legal circumstances surrounding the custody of the individual, including pertinent details about their transfer, identity, and any conditions that need to be observed during their custody.

Having this document ensures that all personnel involved in the supervision and management of prisoners are aware of the individual's status and specific legalities, enhancing the safety and security of both the prisoner and the installation. It also facilitates communication among different agencies and ensures compliance with regulations regarding the treatment of individuals in custody. The other options, while potentially relevant in different contexts, do not fulfill the specific legal and procedural requirements set forth for the custody and management of prisoners in this scenario.