Abstract: A transparent plastic slide for microscopic examination of fluids with at least one grid defined on the floor portion of the slide. The grid consisting of lines rising symmetrically from the floor portion of the slide with a line width of from about 0.05 to 0.005 mm. The lines defining enclosed areas, in which particles suspended in sample fluids can be counted. The sizes of enclosed areas being selected to be within the field of view for microscopic examination.