Though widely used as a blotting paper, 3MM Chr is also used both in electrophoresis and for general chemistry. A medium thickness paper (0.34 mm) used extensively for general chromatography and electrophoresis. Flow rate is 130 mm/30 min. Grammage (gsm): 185, typical thickness (µm) at 53 kPa: 335, gurley (sec/100mL/sq.in): 20, wet burst (ins H20): 12.