Whatman 6869-2502 GD/X 25 mm Syringe Filter, nylon high charge (positive), nylon filtration medium, 0.2 um (150 pcs) Regular Price: $505.85. Price $439.87. Add To Cart. Whatman 6887-2502 GD/X 25 mm Syringe Filter, regenerated cellulose filtration medium, 0.2 um (150 pcs) Regular Price: $646.72. Price $562.37.