Intended for repair of damage to the knife's egg. Provides a basic sanding, but to get the edge sharp you need a finer brow.
The purpose of the grinding determines which grit you should choose. Satake's grindstones are color-coded to clarify which grit the stone has. To make it even easier, the packaging has the same color as the stone.
This is a 240 Grit whetstone.