This pencil is really quite unique. It was designed to be used wet or dry. When used wet, you can create washes blending from dark to light. What is less known about this pencil is that it has an oversized core, bound in cedar. When you sharpen it, you get an extra long point, which facilitates the use of the pencil on its side. Shading and thick lines are much easier to draw than when using regular-core pencils.
Since the cap is metal, an external eraser is needed – perhaps a white eraser and a kneaded eraser.