Smooth-sanded, over-sized beech wood Jumbo Sensory River Stones feature inset, nature-inspired textures. Children 2 and up can engage in sensory play while practicing stacking and balancing and strengthening their tactile differentiation. A beautiful, subdued color palette furthers the possibilities for organic connections during natural play. Smallest stone measures 13cm W x 6.5cm D x 3cm H, largest stone measures 19.5cm W x 9.75cm D x 4.5cm H.