Sanmai(Three-Piece) is a common construction for double bevel knives where two pieces of softer cladding steel are forgewelded to each side of a harder core steel. The harder but more brittle core steel will form the hard cutting edge after heat treating, and the softer cladding will support the core to increase the overall strength of the blade.

The soft cladding enables the thinning process to be a lot easier than a honyaki or monosteel construction. And in the case where the cladding steel are stainless in nature, it can offer protection for the carbon or semi-stainless cores against rusting and discoluoring.

The "nashiji finish" on Japanese kitchen knives refers to a unique, textured surface finish that resembles the skin of an Asian pear, which is known as "nashi" in Japanese. This finish is achieved through a specific hammering and polishing technique, giving the knife blade a distinct, matte appearance with a slightly uneven, tactile surface. Beyond its aesthetic appeal, the nashiji finish also provides practical benefits. It helps to reduce food sticking to the blade by creating tiny air pockets between the food and the steel. This finish is commonly found on traditional Japanese knives, such as santokus and nakiris, and is highly valued for both its functional and visual characteristics, enhancing the overall culinary experience.