This set features a selection of 25 smooth beechwood building blocks and 14 translucent acrylic cubes in 7 colors. These blocks are carefully designed for open-ended construction activities. The translucent acrylic cubes fit inside many of the building blocks for added sensory stimulation. These blocks are perfect for color recognition, descriptive language, calming sensory play and more. Use them as a construction tool for older kids or a simple balancing tool for younger children. The storage tray features guidelines for easy cleanup and storage. For ages 3+. Size of largest block: 3.9"L x 3.9"H x 1"W. Size of tray: 10.7”L x 10.7”W x 1”H.