The Z2 COULTER COUNTER is the latest addition to the Z Series COULTER COUNTER. In addition to reporting both count and concentration results, the Z2 adds the ability to provide size distribution of the cell population. The Z2, like the Z1, uses the Coulter Principle (Electrical Sensing Zone Method) of counting and sizing of cells. This technique provides accuracy, speed, versatility and reproducibility. The Z2 displays the entire size distribution graph, or the size statistics and counts between user selectable areas of the graph. In addition, this instrument displays the cumulative count and the cumulative number % above and below a size determined by the cursor positioned on the graph.