Designed to promote pincer grasp, finger isolation and strengthening. Also, a nice quiet fidget! Individuals maneuver a 3/8" diameter stainless steel (marble) ball through a stretchy cloth maze using their fingers. This is a good bilateral hand activity as well as a visual tracking activity. The stainless steel ball is enclosed within the maze and cannot be removed. Hand washing and air-drying is recommended. Measures 9" x 15". New design, #II recently added with more curves and zig-zags than #I.