Its shape is similar to that of a Ferris wheel, but with seats that are enclosed and rock and roll as the ride rotates.

If the rocking builds sufficient momentum, the seats will flip upside-down and roll end-over-end.

There is usually a manual hand wheel inside that the riders can use to lock the seat and prevent it from rocking.

Some of these traveling examples have had their standard 'egg' shaped cages replaced with front-facing open cars.

These rides are known as "Sky Dancer", "Hi Impact", "The Cages", or sometimes colloquially as an "Egg Roller".