The 440 Mino Sharp Plus knife sharpener is slightly larger and more sturdy in construction than the 220 MinoSharp. The 440 is intended for heavier use. Like the 220, the 440 has two sharpening slots which are pre-set so you can get a perfect edge on your Japanese knives. The separate slots feature a coarse grit and medium grit wheel for a truly fine edge. Each wheel rotates over a small water reservoir to keep the blade clean and cool while sharpening.