I've never used a high-speed steel plane, so according to my research: Steel Material: SKH-3 is a high-speed tool steel containing tungsten, etc., and is characterized by its resistance to heat and its ability to maintain sharpness. Sharpness: Compared to carbon steel planes (such as Yasugi steel), the sharpness lasts longer, and it can smoothly plane even hard wood without chipping. Toughness: In addition to being hard, it also has toughness, so it has the advantage of being less prone to chipping. Applications: It truly shines in difficult situations where the characteristics of the wood change rapidly, such as continuously planing from the white wood of cedar to knots, and then to the next white wood. The weld line looks very much like an industrial product. Also, according to the following site, it seems that you can sharpen it in the same way as a regular plane. https://yamanikohan.shop-pro.jp/?pid=156300727 It doesn't seem to have been used much, and it has a handmade leather cover, so I think it was used with care. As with any tool, you won't know its quality until you use it, so I think it's a good idea to try it out. Please refrain from price negotiations, excluding bulk purchases. Also, please consult in advance for bulk purchases.