Managing Stack Sizes with Stack Upgrades and Downgrades

What stack upgrades change

Stack Upgrade Starter Tier, Tier 1, Tier 2, Tier 3, Tier 4, and Stack Upgrade Omega Tier raise how many items fit in a single backpack slot. Higher tiers hold more per slot. Install one in an upgrade slot and the backpack's storage behaves accordingly.

Converting between tiers

You do not craft each tier from scratch. Use the Stack Upgrade Conversion items to move an existing stack upgrade up. Available conversions: Starter Tier to Tier 1, Starter Tier to Tier 2, Starter Tier to Tier 3, Starter Tier to Tier 4, Tier 1 to Tier 2, Tier 1 to Tier 3, Tier 1 to Tier 4, Tier 2 to Tier 3, Tier 2 to Tier 4, and Tier 3 to Tier 4. Pick the conversion that matches your current tier and your target tier.

Reversing with downgrades

If you need a lower tier back, use Stack Downgrade Tier 1, Stack Downgrade Tier 2, or Stack Downgrade Tier 3. These reduce a stack upgrade to a lower tier so it can be reused or converted again.

Practical slot planning

Combine stack upgrades with Filter Upgrade or Advanced Filter Upgrade to control what enters each slot, and with Pickup Upgrade or Advanced Pickup Upgrade to fill the backpack automatically. Void Upgrade or Advanced Void Upgrade clears overflow. Deposit Upgrade or Advanced Deposit Upgrade empties the backpack into nearby containers. Restock Upgrade or Advanced Restock Upgrade pulls items back out to your hotbar when you need them. This keeps large stacks useful instead of just full.