Imperial Japan
Medals and
Badges
Army Armaments
Badge
The inscription on the badge and the box reads 'Technical Skills Badge, Army Armaments
Administrative Headquarters and the Units under the same Command.'

There were at least two classes,
Kou [1st Class] and Otsu [2nd Class], both shown below.
You can see differences in the design elements.

I'm not really sure about this badge, but this HQ group was formed in October 1942. Before
this date, there were three groups concerned with weapons development, weapons storage,
and technical research. On October 15th, 1942, these three units were merged into one, and
the last phrase on the box and badge appears to refer to that merging.

If you can read Japanese, there's an interesting webpage about this Armaments Unit
HERE.

The HQ Commander of this group reported directly to the Minister of the Army. There were
only three HQ Commanders of this group:

Osuda [Katsutsugu?]: From Showa 17 [1942] 10/15

Kimura Heitaro : From Showa 18 [1943] 3/11  

Suga [Naritsugu??]: From Showa 19 [1944] 8/3

This HQ group was disbanded on April 1, 1945.
Kou [1st Class]
Kou [1st Class]
Otsu [2nd Class]