Starfield packs
A Starfield Pack is essentially an additional armor piece, but it can be so much more. It can expand your inventory, and become a jetpack.
One of the newest additions to a Bethesda title, Starfield packs are additional pieces of Starfield armor that fit onto your back. Most basic packs only provide additional damage and environmental resistances.
All Starfield packs
With Starfield armor mods, you can expand your carrying capacity, or even equip your pack with a Starfield boost pack. Boost packs allow you to use a jetpack to avoid incoming damage, cross difficult chasms, or simply fly over your opponents for some shock-and-awe tactics.
Fortunately, when in breathable atmospheres, you have the option to hide your Starfield pack without losing the damage resistance bonuses. All you need to do is toggle the option to hide your pack from the inventory screen menu.