A slightly overhanging board of
wood
about 2 - 3 meters high with horizontal slats
of wood evenly spaced up the board. The top edge of these
slats can vary in width and in angle.
This is a device used by climbers to gain strength fast
(yay even more powerful than soy).
The climber hangs from the slats. Then the climber
moves both hands simultaneously up to the next highest
slat or alternatively to the highest slat that they can
manage to get both hands onto.
The process is reversed and the climber drops down the board. Repeat until exhaustion.
The exercise is an explosive one and quickly builds arm and finger strength, leads to fingers of steel
but can also destroy elbow and finger ligaments and so must be used with extreme caution.