Two versions of the watch fobs are known: silvered and bronze.
Silvered version.
Obverse
陸軍特別大演習記念 - Army Special Large Maneuvers Commemorative
reverse
in the center
大正七年 - 1918
戊午之秋 - 55th Year of the Sexagenary Cycle [i.e. Year of the Horse], Autumn
around the perimeter
衛兵 - Guards...