Similac Advance Stage 1 Powder Formula Is A Nutritionally Complete Infant Formula Featuring Optigro, An Exclusive Blend Of Brain- And Eye-Nourishing Nutrients For BabyS Development. Similac Advance Is Designed To Support Your BabyS Developing Immune System, Brain, And Eyes, And To Help Build Strong Bones. ItS Milk-Based And Iron-Fortified.