The Sensory Genius collection allows busy hands to be productively active so the mind can focus. This classic toy never ceases to amaze. A simple bend of the wrist is all it takes to send a wooden tile cascading down the ladder. Bend your hand back and the next tile goes tumbling down. This optical illusion will keep kids and adults mesmerized and wondering how it is even possible. Beautiful wooden construction provides an enjoyable clacking sound with every twist of the wrist.