Total area of ruling: 9,0 mm².

• Counting erythrocytes corresponds to Thoma method
• Counting leucocytes in five large squares of 1 mm² each
• Nine large squares of 1 mm² each correspond to Neubauer ruling

The central square of 1 mm² contains, owing to the closer intermediate lines, 25 squares of 16 mini squares 0,05×0,05 mm each.