Backpack

The Backpack is a feature introduced in Portal 2 for Robot Enrichment and is the player's personal inventory for in-game items. Items are kept in individual slots and can be viewed, moved or deleted from within the backpack interface. Items are displayed as pages, with each page displaying 50 items, and initially 6 pages. The Backpack allows the player to manage items used to customize the main characters Atlas and P-body (in co-op mode), which includes Miscellaneous items, Hats, Skins, and Gestures.

The Backpack was introduced with the launch of Portal 2, in April, 2011.

The Loadout Interface
The loadout screen shows previews of equipped Miscellaneous items, Hats, Skins, and Gestures for P-body and Atlas, and allows the player to select new items to attach to either robot.