Are the contents of a BOH still on the same plane?

[Stryyke]

I was looking at using the "called" mechanism from MIC, and it specifies that the item must be on the same plane. A bag of holding creates an extra-dimensional space; so is that space separate from the planes, or part of the current plane?

[KillianHawkeye]

No. Extra-dimensional literally means "outside of this dimension". Think of it like a tiny demi-plane where you can keep stuff.

[Necroticplague]

I was looking at using the "called" mechanism from MIC, and it specifies that the item must be on the same plane. A bag of holding creates an extra-dimensional space; so is that space separate from the planes, or part of the current plane?

Nope. It's called a non-dimensional space for a reason. it's literally not in any other. A BoH (and similar items) can be best thought of as tiny demiplanes, with the mouth acting as the portal to it.

(Side note: Bags of holding create non-dimentional spaces. You're thinking of Portable Holes that create extradimensional spaces.)

[Fouredged Sword]

Nope. It's called a non-dimensional space for a reason. it's literally not in any other. A BoH (and similar items) can be best thought of as tiny demiplanes, with the mouth acting as the portal to it.

(Side note: Bags of holding create non-dimentional spaces. You're thinking of Portable Holes that create extradimensional spaces.)

That is also why objects inside a bag of holding do not interact. It is non-dimentional, as in lacking dimentions. You cannot measure the inside per-say. Objects are suspended in a spaceless void isolated and unable to interact with anything. The volume restrictions are not contingent on you teterising the contents into the listed space, each object simply ticks off the total.