Backpack

Backpack is one of the items that can be found in The Culling.

Equipping it increases your item slots to 5, making it better than the Crafted Satchel (4 slots).

There's also a Perk for starting with a Backpack.

Upon dying, the Backpack is dropped and can be picked up by other players.

You can also combine the Backpack with a Rock to create Crafted Body Armor.