The two slots on a knife sharpener are designed to accommodate two different types of blades. Many people believe that the slots are there for sharpening Japanese style blades, while others believe that the slots are for sharpening American style blades.
The truth is that the slots are actually meant to accommodate both types of blades.
The Japanese style blade is typically much thinner than an American style blade, and the slot on a Japanese style sharpener is specifically designed to sharpen those type of blades. American style blades, on the other hand, are thicker than Japanese style blades and the slot on an American style sharpener is meant to sharpen those type of blades.
The truth is that both slots can sharpen any type of blade, but if you want to sharpen a Japanese style blade then you should use the slot on a Japanese style sharpener and if you want to sharpen an American style blade then you should use the slot on an American style sharpener.
