Align the grooves and rotate the two halves in opposite directions.
To keep your mind working for hours on end.
A challenge only for the most daring.
Warning: Last items in stock!
The popular Brainstring has turned upside down! Brainstring 'R' is as knotty as the original, but has a movable ball with a 360 ° spin that will have you on the ropes.
Recommended Age: +7 years
Logic, Strategy, Focus
How to play