The horizontal and vertical pieces of each grid block can be placed inside each other, which provides great stability for construction play. Houses, Castles or other structures can be built with these amazingly shaped blocks. In addition, other Bauspiel products, like the Acrylic cubes can be added as windows in each block. Stained lattice blocks are made of solid Alder wood and measure 17.5 x 17.5 x 2.5cmH. Please note that price is for one grid. Colour chosen at random. Should you purchase more than one, we would give mixed colours. There are only two of each colour in a box.