4moms rockaRoo™ BIG motion, small size™. The 4moms rockaRoo provides a front-to-back gliding motion that babies love in a compact size. Its sleek, modern design is 70 percent smaller than traditional swings, so the rockaRoo looks great in any home. It features five speeds, a mp3 hookup and reversible toy balls. Babies like a variety of motion and 4moms now gives parents more options, from the natural up and down and side to side bouncing and swaying motions of the mamaRoo to the smooth, front to back gliding motion of the rockaRoo.