Hole 1 shaves just the pencil’s wood casing , exposing (but barely touching) the graphite. You are left with a cylinder of graphite sticking out of the pencil tip, as shown below.
Hole 2 sharpens the graphite to a point, but does not shave the wood.
You can easily control the sharpness.
When it’s time to resharpen, I try hole 2 first. I can usually get a few sharpenings this way before I go back to hole 1. Because of the way it sharpens, pencils last much longer. — Mark Frauenfelder
Kum Two Hole Automatic Long Point Pencil Sharpener $7 Also available from Pencils.com as a Blackwing-branded sharpener.