A Finnish spinner. The reason we choose this from among the many spinners is that this spinner can simulate the spin of figure skating. This spinner spins the most compared to other spinners when used outdoors. The secret is that the rocker curve is designed just like a rocker on a skate blade, and it is easy to find the position and center of gravity, and how to put weight on the ball of of the foot when rotating. The spin of figure skating is a movement that uses the moment of inertia. Therefore, you can get a feel of a spin mechanism by practicing to see how the rotation speed changes when you open or tighten your arms. Some American clubs have developed a spin-based figure skating programs and sent competitors to the US Championships.