4Hurry! The firemen must put out a fire--thank goodness for the siren, ladder, hose, and the fire truck that will get them there! Our Zippy Wheels series celebrates young children's fascination with all things big rig, helps them learn some interesting things about their favorites, and even comes with rotating wheels. From fire trucks that help save lives, to dump trucks that drop heavy loads, to tractors that help around the farm, and diggers that clear the ground, there's always something to learn and see here.