Part of the Grimm's 4x4 Series, the Counter-Rotating Stepped Spiral is fantastic to use in building up mysterious spiral staircases in a palace or to create a tower with a steep staircase or to make an imaginary place accessible. This set make ideal room "decor" as it invites everyone to play. By building and playing with these blocks, children develop fine motor skills and spatial thinking skills. 56 building blocks on a wooden plate. Materials: lime wood, non-toxic water based color stain/non-toxic plant based oil finish.