Joint Japan-Manchukuo Air Defense Badges

1st design pattern.

1st variation.

Obverse

防空 - Air Defense

 

2nd variation (by stamp and enamels).

Size 17 mm.

 

Additional examples of 2nd variation.

Size 17 mm.
Thickness 4 mm.

 

2nd design pattern.

Reverse is plain.

 

Very same badge at the postcard from 1935.

Mukden Air Defense Maneuvers in Manchukuo.
"Military & civilian to unite for the air defense!"

 

3rd design pattern.