Santoku is a cross between a chef's knife (gyuto) and a chopping knife (nakiri). The tip of the blade, which is directed down from the center of the knife, makes it possible to find a more stable support and a larger cutting surface on the working surface. Well suited for cutting and shredding meat, fish, root and fruit. Santoku is a very popular common knife in Japanese homes.

The blade of Sakai Takayuki Aonikou knives is made of high-quality Blue#2 high-carbon monosteel. Blue#2, also known as aogami or blue carbon steel, has premium cutting properties and long-lasting grain resistance. Aonikou knives have a "full-tang" design that passes through the handle and is fastened with three rivets. The metal bolster ensures that the knife is well balanced and not feathery. The Western-type handle is made of brownish pakkapuu.

Aonikou knives have double-sided 30/70 sharpening. This means that the cutting phase on the right side of the knife blade is larger than on the left side Thus, when taken from the box, the knife is more suitable for right-handers, but if desired, it is possible to sharpen the knife around 50/50 or with a 70/30 phase suitable for left-handers.