8 building block Reusable Cups with Straws - Party Cups by fun express Build the best birthday party ever! Perfect for keeping kids hydrated while they play. Great grab and go party favor. 8 cups per order - 2 each of red, blue, yellow and green. Each measures 3 x 2 x 4.75 inches with a 7.5 inch flexible straw; 16 oz. capacity.