4moms mamaroo classic grey parents dont vibrate like bouncy seats or swing like swings they bounce and sway and thats what the mamaroo does it moves like you do its the only infant seat that has five different motions to choose from as well as being bluetooth enabled allowing you to control both the motion and sound of your mamaroo remotely from a smart device just like the classic the plush seat is machine washable and easy to zip in and out of your mamaroo