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. Add to Cart. Add to Wish List. Whatman 6875-2502 GD/X 25 mm Syringe Filter, PTFE filtration medium, 0.2 um (1500 pcs) Regular Price $2,733.72 Price $2,374.02.