The 1988 S Annual 5 Coin Proof Set includes coins made of copper, struck in proof quality in San Francisco. This set comes in its original United States Mint box with a Certificate of Authenticity. Each coin is guaranteed to be in uncirculated condition, adding to its collectible value for numismatists and coin enthusiasts. The set is a comprehensive collection from the U.S. Mint, showcasing the craftsmanship and details of American coinage from 1988.