See also https://asiamedals.info/threads/2nd-flight-reserve-trainee-a-class-yokaren-program-graduation-commemorative-watch-fob.28422/ ; https://asiamedals.info/threads/4th...raduation-commemorative-watch-fob-2600.27017/ ...
Watch fob from a personal collection.
Obverse
機関 - Engine
reverse
皇紀2601年 - 1941
陸軍航空整備學校 - Army Aviation Maintenance School
第二十一回 - 21st
乙種學生 - B [Otsu] class [Aviation Mechanics Flight Reserve] Trainee Class
Engraved
鉾之原 - Hokonohara
In 1928, a new program was created to enable...