Named for the sacred sword carried by Japan's Samurai warriors, Calphalon Katana Series cutlery has its roots in a centuries-old tradition of superior cutlery craftsmanship. Like the awe-inspiring swords wielded by the Samurai, Calphalon Katana Series cutlery is crafted using a time-honored layering process that creates a Damascus style blade, clad with 33 stainless steel layers. This unique series of cutlery uses VG Japanese steel, which provides exceptional sharpness and ultimate edge retention. These knives also feature a patented integrated bolster design and an ergonomically designed poly-resign handle. Our Diamond Steel is coated with monocrystalline diamonds for exceptional hardness which allows it to actually sharpen knives. Use your steel every time you put your knives to work. When sharpening a knife, position your steel tip-down against a cutting board. Hold the knife at a 22 degree angle to the steel and draw it across from heel to tip in one smooth motion. Repeat 3 or 4 times per side.