Only used for a month or so for one baby. A mobile to attach to crib and can be heightened or lowered as needed. Can also be turned outside the crib to eliminate distractions while sleeping. The Wimmer-Ferguson Infant Stim-Mobile for Cribs Introduces baby to high contrast images and colors for early visual and multisensory development. Ten interchangeable graphic cards offer a range of simple high-contrast images to more complex colored patterns and graphics to foster visual development. Graphic cards are labeled by age to guide you with recommended graphics to use as baby's vision develops. Adjustable cord on the Infant Stim-Mobile allows you to easily change distance of graphics from baby as their vision develops. Baby toy suitable for newborns up to 5 months old; Wimmer-Ferguson toy graphics and designs are based on scientific research of visual development in early infancy.