Helps with blood cell analysis that comprises of diluting a whole-blood sample with a solution that functions as a diluent. The diluent (Reagent 1) provides the ability to analyze portions of the diluted blood sample for different blood cell types, such as red blood cells and platelets. When combined with the lytic reagent (Reagent 2), the diluent (Reagent 1) is useful in the quantitative determination of hemoglobin, the enumeration of leukocytes (white blood cells), and the derivation of leukocyte subpopulations.