All of these peripheral blood cells have different characteristics. In order to accurately identify each of them, a peripheral blood film must be made, preferably from capillary blood or blood anticoagulated with EDTA (Ethylenediaminotetracetic Acid). EDTA, in contrast to many other anticoagulants, preserves cellular morphology. The individual characteristics of each cell type are made visible by staining the blood films with the Wright stain, and observing them under the microscope.