GVS Life Sciences 1224127 Non-Sterile Syringe Filter, FLL/MLS, GF/NY, 0.22 µm Pore Size, 30 mm Diameter (Pack of 50): Amazon.com: Industrial & Scientific
Sartorius 11406-50-ACR Membrane Disc Filter, Cellulose Nitrate, Sterile, White with Black Grids, 0.45 μm, 50 mm (Pack of 1000): Amazon.com: Industrial & Scientific