The glass marker boards come in a variety of useful sizes. These magnetic glass boards come in 12″ x 24″, 12″ x 36″, 24″ x 36″, 36″ x 48″, 48″ x 48″, 48″ x 72″, and 48″ x 96″ sizes. The smaller 24″ x 36″ and 36″ x 48″ dry erase boards can be used vertically or horizontally. You can get more details about these dry erase boards here.