This is the replacement blade for the Gyokucho Fugaku Dozuki Super Hard (No. 110), the 240 mm folding crosscut back saw in the Fugaku line.
It has the same specs as the blade on the saw: 0.3 mm thick, with crosscut teeth at a 1.5 mm pitch (16.9 TPI) and a rounded rip-tooth tip for starting cuts in the middle of a panel. When the teeth dull, fit a new blade and keep your beech handle.
Gyokucho saws are made in Miki, Hyogo, by Razorsaw Kogyo, which was set up in 1969 when it developed the replaceable-blade saw. Gyokucho Sangyo, its sales company since 1975, sells them.