Backpacks are portable inventory chests that can be crafted like a regular chest. They can be worn with a player’s outfit or placed on the ground and can carry up to 27 slots of items, just like chests. Unlike chests backpacks can be renamed and can have their contents inspected in any GUI by Shift + Right Clicking. Backpacks can also be recolored with dye or resized.
Some backpacks offer unique functionality, such as the Squid backpack that allows players to breathe underwater and see in caves, the Cow backpack that makes milk when the player puts wheat in it, or the Library backpack that grants a higher enchantment level at enchanting tables when it is close by. Other packs can be deployed anywhere, to provide an instant tool swap, fluid tanks, or additional storage space.
Tools stored in the special backpack tool slots render on the backpack and can be rotated by sneaking and using the mouse wheel. These tool slots can accept Tinker’s Construct tools, Thaumcraft tools, Buildcraft tools, and more. The hose can be used to suck, spray or pour liquids in the world, depending on which action is selected when the player equips the backpack. It can be refilled from other sources such as a water bucket.
Backpacks can be recolored by placing 1 piece of dye alongside the recipe for the item in the crafting grid. Alternatively, they can be resized by shifting + left clicking the item while wearing it or by placing it on the ground.