Each 4-pack comes with a rare or hyper-rare mystery Bitty Pop! to complete the series. The Bitty Pops! come in hard acrylic cases with removable bottom lids. The removable bottom lids serve as the acrylic base, to which the Bitty Pop! figures attach. Your favourite Pops! have become Bitty Pops! Expand your collection with this assortment of Bitty Pop! figures of your most beloved cartoon characters.