Material: glass. For leucocyte, thrombocyte and erythrocyte counting. Double counting grid. Counting grid with nine large squares. The four corner squares are used for leucocyte counting. The smallest square in the centre is split into 25 group squares and these in turn are split into 16 small squares. Five of the group squares are used for erythrocyte counting. Large square: 1 mm 2 Group square: 0.04 mm 2 Small square: 0.0025 mm 2 Counting chamber Neubauer improved Dark lines, 2 spring clamps The counting grid appears under the microscope as a grid of dark lines. Spring clips securely fix the coverslip to the counting chamber. In vitro diagnostic medical device class A Delivery incl. two haemocytometer coverslips (20 x 26 mm).