Possible Clues:

• Endorsement allowing bearer to enter country
• Pass is needed in the Victoria and Albert
• Certain plastic
• Stamp affixed to passport as permission to enter country
• Is admitted to part of US, having this?
• Endorsement one's required to enter Atlantic state
• Endorsement is needed in eastern state
• The way four is back for permission to come in
• You may need this to get permission to travel round by way of the South
• Passport stamp or well-known credit card