They're things that have more space inside than they look on the outside. So, an 'Arms Band' looks like a bracelet, but you can store a lot of larger things inside. My ghost pouch is the same- since it's an item I found in a ghost room, space works different for it, so I can put more in it than it would have normally held.
[ahem]
Basically, we could probably put a lot of containers of water in one of those!
just fill a hammerspace object with numerous barrels of water lapis its fine
They're things that have more space inside than they look on the outside. So, an 'Arms Band' looks like a bracelet, but you can store a lot of larger things inside. My ghost pouch is the same- since it's an item I found in a ghost room, space works different for it, so I can put more in it than it would have normally held.
[ahem]
Basically, we could probably put a lot of containers of water in one of those!