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Kleve indeed :D

why? dunno hahah cause the hole is round but why ?

Because a round cover can't fall in, no matter what angle and orientation. A square one can. Great engineering thinking, that, I like it.

really?
hmmmm ...

Try it with some round and square Tupperware-like stuff if you don't believe me.

Usually when you see a square cover it has hinges to attach it, round covers don't need that.

oh, you're right! ^ ^

Duh.

Heehee. You tried it?

yes, with a lunchbox haha
I should so I did :D
nothing to loose haha
I did yesterday and I had to laugh