Staedtler Pencil Sharpener

I know how to use the first big hole, but what are the three smaller ones for??

Staedtler pencil sharpener,
http://www.staedtler.com/sharpeners.Stae ...
http://www.staedtler.com/tub_sharpeners_ ...

may depend on size version you have, pens of different sizes require different angles to sharpen the point, short and broad with round point, or long and narrow with the pin point,

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Small holes for grinding of different sizes of pencil technique leads

different sizes of pencils, colored pencils, penis, etc. ...

they are different size pencils. such as pencils manufacturers.