Steel : High Speed steel??? Black smith : Yoshio Usui. Handle : Red oak. The characteristics of this chisel are the hardness of high speed steel and the three grooves on Hollow back. This groove has a role. 1, Less material to remove when you flatten the back of the chisel. The hollow back makes it much easier to get it flat and makes sharpening it in the future faster and easier. Helps the blade to be more precisely horizontal and vertical when processing wood. Processing this Hollow back requires high technology. It is more effective if there are more grooves. This feature is unique to the Japanese chisel. HSS is so hard that it is difficult to grind, but you can grind it with a diamond whetstone. You can keep the sharpness even in hard work. It requires skill, but it can be sharpened like White steel. I finally had some time to sharpen the HSS chisel. It sharp easy on my diamond stones and it got very sharp. I then tested it on some American white oak and some Baltic Birch plywood which has many layers. It held up for about 50 hard hammer hits before the edge deformed & dulled. I was happy with the performance as those are 2 very hard materials and the plywood has glue and who knows what else in it. We will send you a new invoice and offer a discount. International Buyers – Please Note. ·We do not mark merchandise values below value or mark items as gifts US and International government regulations prohibit such behavior. Please see our other items. Please find a best item in.