Faber Castell Free Ink Roller Rollerball Pen 0.5mm

Here’s another reason why the humble pencil is superior to pens, biros, ballpoints and rollerballs.
Pencils can write underwater. Go on, try it! Obviously paper wouldn’t be your first choice of writing surface, but it may last long enough to prove the point.
They can also write in zero gravity, but that one may be a bit harder to test.

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