This premium Nakaya Ryoba saw is a veritable multi-purpose tool!
Ryoba saws feature two cutting sides - one for ripping and one for cross cutting, hence the "Wonder-Saw". The blade stock is slightly thicker at a whopping 0.45mm (!) and lacks a rigid spine allowing full through cuts on thicker or longer stock, whether ripping or cross-cutting. The holes in the blade are said to reduce friction in through cuts. Be it by this special design or another, we can attest to the cutting ability of this blade!
The specially hardened Japanese teeth are multi-faceted on the cross-cut side in the style of Dozuki saws, while the ripping side are a more traditional looking handsaw tooth style though in a variable pitch arrangement - both sides cut extremely efficiently on the pull stroke, as per the Japanese fashion.
This model has a 240mm blade which is fully replaceable, set in a traditional rattan wrapped timber handle.