The answer is Guam, and the Philippines islands.
The treaty signed after the victory of the U.S. in the Spanish-American War was the Treaty of Paris (December 10, 1898). In the Treaty, not only Spain renounced its claim to Cuba, which later became a protectorate of the U.S., but also ceded Guam, Puerto Rico, and the Philippines islands, this latter was sold for $20 million approximately.