Whatman Nuclepore Hydrophilic Membrane, 0.4 µm Pore Size, 25 mm Circle, 100 Pack, 10417106. Regular Price $100.34 Price $87.13. Add to Cart. Add to Wish List. Whatman Nuclepore Polycarbonate Black Membrane Filter, 0.2 µm Pore Size, 25 mm Circle, 100 Pack, 110656. Regular Price $137.59 Price $119.49.