Mad Triad Challenge
a.k.a. Twisting Tri-Side Puzzle
Patented by Heng-Chun Ku 2000, copyright Playroom Entertainment 2002,
Made by Dah Yang Toy Industrial Co., China.
(plastic, 5 inches)
Turn the knobs to rotate a circle of six triangles.
Mix up the puzzle and then restore it to six colored wheels as shown above,
or make different patterns such as those shown below.
presents a solution.
from: www.uspto.gov - patent no. 6,022,021