So you have one of our sail carts with adjustable sail and are all set to demonstrate Newton's laws of force and reaction but there just is not enough wind in your classroom. What do you do? Don't fret it is a breeze with one of our 6" portable fans. With a quite motor and multi speed control this fan has plenty of power to move that cart all over the classroom. Comes with a sturdy base but is light weight so that it is easy to create any angle of wind against your sail.