Parents don't vibrate like bouncy seats or swing like swings. They bounce and sway, and that's what the mamaRoo does: it moves like you do. The 4Moms team used motion sensors to measure the movements of reals moms and dads as they soothed their babies, and replicated those motions in the mamaRoo. It's the only infant seat with five different motions, all modeled after the natural movements parents make to comfort their babies. The mamaRoo plush is the same great mamaRoo with a softer, plush seat fabric that's even more comfortable for your baby. Just like the classic, the plush seat is machine washable and easy to zip in and out of your mamaRoo.