Derwent : Graphitone Watersoluble Graphite Pencil : 4B

It’s a pencil-shaped stick of pure, artist quality water-soluble graphite which can be used just like a conventional pencil or broken into chunks to create broad sweeps of tone or subtle graphite washes. Available in four versatile wash strengths, Graphitone is easy to use as its protective wrap simply peels away to expose as much or as little graphite as you need. And because the entire stick is 100% useable material, it’s very economical too.