This is a 245mm gyuto with a 1.2519 core and wrought iron cladding.  The 1.2519 core steel is German Tungsten tool steel which is quite similar to blue2 (aogami2).  The cladding is a pure form of iron which has been etched reveal the brilliant detail of the clean iron.  There is a piece of pure nickel separating the cladding and the core steel which minimizes carbon migration. The handle is spalted two-tone maple burl. The ferrule is African Blackwood.
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Spine Measurements:
Out of the handle: 4.45mm
Above Makers Mark: 2.60mm
Middle: 2.02mm
4cm from tip: 1.97mm
2cm from tip: 1.51mm
Weight: 208g