Shop Print Media, No drawers, For Calibration of the Serum Sodium, Potassium and Chloride Assays, Dry Pro™, 20 Unit / mL, 55% Cotton / 45% Polyester, 1.27 mm Inner Diameter / 2.9 mm Inner Flange Diameter / 2.9 mm Outer Flange Diameter / 1.4 mm Inner Flange Distance / 2.1 mm Total Length