Mobile Diving & Salvage Unit 2. Condition : Used and in good condition. This coin is 2 inches in diameter. 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 “Commander Mobile Diving & Salvage Unit 2 Deep Sea Diver Navy Challenge Coin” is in sale since Thursday, August 10, 2017. 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.