It's so difficult to tell how big things are from measurements. I just made a box up that was about the same size as that, turns out that a sheet of A4 paper is 30cm, so that helped. That's pretty huge!
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Welcome, my handsome LH syrian boy Dr Calcifer Lightman (a.k.a "Cal")!
Run free at the bridge my precious little Senpop. (10/10 - 04/12)
RIP My sweet little dwarfies - Doc and Noodle <3