This set of 4 wooden boards comes in a box. It introduces the child to the tactile differences. Each of the boards is different in the way they teach roughness / smoothness-
Its half rough and half smooth and introduces the contrast between the two.
It has alternate strips of rough and smooth to co-ordinate finger movements and improve dexterity.
Teaches the gradation in roughness from very rough to least rough in five segments.
Gradation in smoothness from the very smooth to the least smooth in five segments