Quadror Large Building Blocks A brilliant building system invented by internationally known designer and architect Dror Benshetrit Children and adults alike can experiment with this ingenious flat-packing geometry that can be used to build super strong walls, towers, houses, and much more The perfect gift for budding inventors, engineers, architects and designers Great for kids and grownups of all ages who like to think outside the blocks Includes 10 building blocks each measuring 3" square