Naniwa P-306 Professional Stone (Chosera) 600 Grit Japanese Whetstone Knife Sharpener The key is the wide

The key is the wide serrations

although they get worn

It is paired with an ultra-lightweight handle made from fiberglass-reinforced nylon (FRN)

While copper is heftier than stainless steel or glass-filled nylon

Naniwa P-306 Professional Stone (Chosera) 600 Grit Japanese Whetstone Knife Sharpener The key is the wideNaniwa's Professional Stone is their highest grade stone and the overseas model of their "Chosera" stone. 600 Grit 210 x 70 x 20 mm Instructions: Splash stone with water before sharpening and continue to do so when sharpening. Naniwa Professional Stones do not need soaking as they have tightly resin bonded particles, making them more durable and effective than other makes. Made in Japan