The Santoku is the Japanese equivalent of the European chef's knife. Translated, Santoku means "three virtues" and can be used for fish, meat and vegetables. Visually, the Santoku is reminiscent of a cleaver, but it is therefore not suitable for chopping. Its tall, stubby blade is sharpened on both sides and is ideal for bulky cuts like vegetables. With the wide blade, the cuttings can also be easily transported in the pot or bowl.

The KAI Seki Magoroku Composite series includes eight different blade shapes. The knives are made from two different types of steel, VG-MAX steel and SUS42012 steel. This creates an exciting contrast on the blade. The two types of steel are joined by a special copper solder, thanks to which a delicate line of copper remains visible on the blade as a special detail. This special composition gives the blade great resistance and extreme precision.

The handle of the composite knife is made of light-colored Pakka wood. The transverse grain and the fine, tapered shape of the handle give the knives a particularly light dynamic. In 2013, the KAI Seki Magoroku Composite received the "reddot design award".