This is the replacement blade for the Gyokucho Komame 180, a fine-tooth dozuki for dovetails and small, precise joinery.
It has the same specs as the blade on the saw: 180 mm long and 0.3 mm thick with a long metal back, 26 TPI teeth hardened to 68 to 71 HRC, a 0.46 mm kerf and up to 1-7/8 in (48 mm) of cutting depth. When the teeth dull, fit a new blade and keep your 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.