Graphing practice on dry erase saves paper! Bold lines separate board into quadrants each 10 squares by 10 squares; total grid is 20 squares by 20 squares. Individual squares measure 1/2" x 1/2". Plain work space is 11" x 5-1/4". Boards feature non-ghosting dry erase surface with rounded corners and smooth edges for safety and comfort. Durable hardboard backing is warp and chip resistant. Measure 11" x 16" x 0.125" Bundle of 4 Dry Erase Boards.