Naval Special Warfare Development Group DEVGRU SEAL Team 6 Navy Challenge Coin. Coin measures 1 1/2in diameter. SEE PHOTOS FOR DETAILS. Thank you for looking. The item “Naval Special Warfare Development Group DEVGRU SEAL Team 6 Navy Challenge Coin” is in sale since Monday, April 29, 2019. This item is in the category “Collectibles\Militaria\Current Militaria (2001-Now)\Original Items\Challenge Coins”. The seller is “wackydeal” and is located in Jacksonville, Florida. This item can be shipped to United States.