The Color Changing Happy Birthday Plastic Cups 16oz Set of 4 in Pink is a fun and festive addition to any birthday party. Made by Cleverworks, these cups feature a happy birthday design that changes colors when filled with cold beverages. Perfect for serving drinks at birthday celebrations, these plastic cups are durable and easy to clean. Whether used for a casual gathering or a more formal event, these cups are sure to delight guests of all ages.