This is probably the thinnest above the edge (yet standard thickness at the spine) knife I have ground to date. The objective was to push cutting performance to a new level, without putting the knife in the category of lasers.
Spine thickness is 3.25mm at the handle, 3mm over the heel, 2.15mm half way, and 1.75mm 50mm from the tip.
255mm gyuto, 52100, 62.5RC. Handle - cocobolo with buffalo horn and N/S spacer. Saya - select grade poplar.