WW2 Imperial Japanese Navy U-Boat Proficiency Badge Gorgeous WWII. Measurement: 1.50 inch in diameter.Complete with working pin and open catch. Nice original piece from my father's estate collection. Check out my other items! This item is in the category "Collectibles\Militaria\WW II (1939-45)\Original Period Items\Japan\Medals, Pins & Ribbons". The seller is "homestead_antiques" and is located in this country: US. This item can be shipped worldwide.