Backpack

The Backpack is an Astroneer's all-purpose storage and small item fabrication solution. It features 8 inventory slots, 2 small attachment points, a small printer, and storage for both oxygen for the Astroneer and power for their Deform Tool.

The various features of the backpack can be accessed by "opening" it, making it larger and easier to interact with. To open the backpack, simply press on your keyboard or  on your Xbox controller, or select the it directly using the cursor.

Inventory Slots
The backpack has 8 slots dedicated to resource and small item storage. Items can be placed into, removed from, and rearranged within these slots manually, but as long as there is an inventory slot available, resource stacks collected with the deform tool or items created using the backpack's printer will be automatically placed there. If all inventory slots are full, newly created or collected items will drop to the ground nearby.

It should be noted that while the backpack's inventory slots resemble attachment points, they do not behave as such. Only a few select items truly "connect" to the backpack through the inventory, such as Tanks, Batteries, and Power Stacks.

Attachment Points
Atop the backpack are 2 small attachment points, which can be equipped with any single-point attachments. These are commonly used to host power sources such as the Solar Panel or Wind Vane, allowing an Astroneer to recharge their backpack's internal battery in the field. Like other attachment points, however, they can also be fitted with resource stacks or other small items for additional storage.

Printer
Using the small printer on the Backpack, simple items can be crafted on the go. As you cycle through the various printable items, the appropriate resource will automatically move down to the printer's input slot if it is already in your backpack. This input slot can be used to deliberately store a specific extra resource if so desired, but be forewarned that changing the item to be printed will eject the contents of the input slot from the backpack if the rest of its inventory slots are already full.

Larger objects can be printed using the Printer Module.

Oxygen and Power Storage
Prominently displayed on the backpack are two gauges: the horizontal oxygen gauge in light blue, and the vertical power gauge in bright yellow.

Enough oxygen is stored for 70 seconds of untethered field work. Running consumes a little more oxygen, making the tank empty in 50 seconds instead of 70.

You get a notification when the tank is 50% and then 25% full. When you run out of oxygen, you are suffocating. Within 5 seconds of starting to suffocate, you cannot run anymore and then you have 10 more seconds to reach a source of oxygen before dying.

The battery stores enough power to use the deform tool continuously for only 8 seconds (without other source of power). Unlike other batteries, the backpack slowly recharges itself at the rate of 0.25 units/sec (4 seconds/units), but its charge cannot be transferred to other batteries.