Blue side of the eraser
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A few years ago it was very common to use a three-color eraser, although it is still on the market today, there are many other models besides this one. But previously, this eraser had a blue side that many people thought was to remove the ink from the pens; but it was true, the real function was to be used on rough sheets.
Something super conventional for artists who needed to get rid of traces quickly, which is why they used this blue side that had the eraser, while the other side was for normal sheets.
