Naval Special Warfare Advance Training Command. Condition : Used and in good condition. Never personally given any of the coins. All coins are guaranteed to be in excellent condition unless otherwise specified above. The free listing tool. The item “Naval Special Warfare Advance Training Command SEAL Flipper Navy Challenge Coin” is in sale since Wednesday, July 6, 2016. This item is in the category “Collectibles\Militaria\Current Militaria (2001-Now)\Original Items\Challenge Coins”. The seller is “rolyat11″ and is located in Panama City, Florida. This item can be shipped worldwide.