This 1966 DDO SMS Kennedy Half Dollar is the finest known with this variety. From 1965 to 1967, the US Mint did not produce Proof issues of the Kennedy Half Dollar series. Instead, Special Mint Sets were struck which have similarities to both Circulation and Proof issues. Similar to Proof examples, Special Mint Set coins were struck using polished dies. Unlike Proof examples these coins were not struck multiple times or individually handled, making high grade examples difficult to acquire. Double Die Obverse coins showcase a doubling on the obverse due to an error in the creation of the die. Only 46 examples of this specific 1966 DDO SMS variety exist and this coin is the finest known example in Mint State 69 condition.