Ten, or so, years ago a small number of these came in from China through Ebay. Before that drawings were about all one could find concerning these grenades. It was replaced by the later Type 91 for knee mortar use. It appears that probably none of these made it out to the Pacific after that replacement. Otherwise, these would have been brought back as souvenirs and would have been shown in US military publications. After that small influx of grenades the supply has again dried up so they are quite rare again. I was lucky enough to pick up four of these and sold two of those to the late Doss White.
Note that the grenade was loaded through the bottom and did not have a removable top plate. Another interesting feature is the short brass fuse cover. The fuse has been deactivated but not burnt out like most were. This left intact the wax exhaust port plug.

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