I introduce to you TierBags, a mod that adds container/inventory bags in Tiers, these bags are added to the mod right now:

Light Leather | 9 slots
Heavy Leather | 18 slots
Copper | 27 slots
Iron | 36 slots
Cobalt | 45 slots
Thorium | 54 slots
Adamantite | 58 slots
Mithril | 63 slots
More bags will be added...

Crafting:

Everything is crafted at the Workstation bench from the Tools category. Every tier will use its previous tier bag to craft with metals and other stuff.

How to use:

Simply hold the bag you want to open in your hand and click right mouse button.

Misc:

As the game, this mod is in early stage, so far it has added bags for some tiered minerals/materials, but I want to add more bags in-between every tier so far. Also I plan to add new tier bags if new mineral/materials for tools/armors is added to the game.

Feel free to suggest any changes to the mod in the comments.

ps: I know the textures on the models is not the greatest as I am no artist, but these will get better with time as I learn more.