Graver is placed in either of two angled openings and rolled over flat oilstone to sharpen.
Graver can be set to any angle by setting index. Holds graver edge in position while honing on oilstone.
Special feature of this sharpener is the elongated shield that holds the graver in an immovable position during the sharpening action. Gravers can be sharpened at any angle. Screw on top locks graver and also serves as a finger rest.