help with capacity

hello everyone- i'm trying to buy my first "pretty" bento box, and i'd like to do it right so i don't eventually end up with a giant pile of rejects. :) unfortunately, the internets and my location are conspiring against me - there aren't any stores here that sell bento boxes, and all the sellers on amazon have sizes listed in cubic inches. most of the ones i like are 2-tiered by kotobuki or hakoya, and they all seem to be around 5"x4"x3". sooo...if any of you out there have a box that even kinda matches that description, could you pretty please tell me how many mL it holds? thanks!
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