Playskool Replacement Ball Set for Ball Popper Toys - Elefun & Busy Ball Popper (Colors may vary) 5 balls included For use with ALL Playskool Ball Popper toys; Elefun Busy Ball Popper, Busy Ball Popper, Poppin' Park, Explore N' Grow Busy Ball Popper, etc. Ball diameter: 1.75" Ages: 9 months and up