Wash painting brushes are similar to the brushes used for calligraphy and are traditionally made from bamboo with goat, ox, horse, sheep, rabbit, marten, badger, deer, boar or wolf hair. The brush hairs are tapered to a fine point, a feature vital to the style of wash paintings.
Different brushes have different qualities. A small wolf-hair brush that is tapered to a fine point can deliver an even thin line of ink (much like a pen). A large wool brush (one variation called the big cloud) can hold a large volume of water and ink. When the big cloud brush rains down upon the paper, it delivers a graded swath of ink encompassing myriad shades of gray to black.
We used this historical aspects to create the best tattoo pigments to achieve those effects on skin.