Kamikoto blades are handcrafted from 420J2 steel (Genten series) and SLD steel (Ganjo series). With a HRC of 53 +/-2, the Genten series offers the benefits of a practical, highly corrosion-resistant blade. We recommend the Genten series to customers who do not mind tending to and sharpening their blades with a whetstone from time to time. While SLD steel is far more likely to chip and rust over time, it compensates with a significantly higher HRC of 62 +/- 2; these knives tend to retain their edge over time.