Children can build gross motor skills and creativities while having fun with this All-Weather Hollow Blocks Set! Moulded from Poly+ material, the lightweight blocks and planks allow for substantial, interactive group builds in muddy, rugged environments. Each piece features thick hollow walls, weather-resistant stainless steel hardware, and soft-touch endcaps that absorb shock as builds are deconstructed during play. This set includes cubes, rectangular prisms, right triangles and planks. Largest block is 24cm W x 14cm D x 14cm H (9-1/2" W x 5-1/2" D x 5-1/2" H).