With double ruling. Calibratable. Cell depth 0.1mm. Counting grid with 9 large squares each 1 mm². The 4 large squares in the corners for counting leucocytes are each subdivided into 16 squares with a side length of 0.25mm. The large square in the middle is subdivided into 25 squares each with a side length of 0.2mm. Each of these is further subdivided into 16 smaller squares each with a side length of 0.05 mm and an area of 0.0025mm². The 5 group squares marked with an 'E' are used to count thrombocytes and erythrocytes. All group squares have triple boundary lines on each side.