Developed as an interim step between a hand-thrown grenade and a full sized crewed mortar, the Type 89 could be carried by a regular infantryman along with their standard kit. While not as stable and precise as the Stokes-pattern mortars used by the Americans, the Knee Mortar could be brought into action very quickly in an emergency, and still used from prepared positions when time permitted. Matching numbers on the tube, endcap, firing mechanism, shaft and baseplate, with the firing mechanism graduated out to 650 yards and a spring loaded canvas dust cover.

Good overall, with traces of the original blue finish, showing a mixed brown and gray patina, some pitting concentrated on the baseplate, and some replaced screws. Some tool marks are present on the endcap and shaft. The dust cover shows some staining and wear. Mechanically excellent. NOTE: This Destructive Device is a National Firearms Act (NFA), fully transferable Class 3, which is registered with the Bureau of Alcohol, Tobacco, Firearms and Explosives, (BATFE) under the provisions of 18 U.S.C. Chapter 44 and 27 CFR part 479, National Firearms Act.