Whatman ® ME Membranes for Microbiological Control, ME24/21, Without Interleaving Paper, Pore Size 0.2 μm, Black Grid, Diam. 50 mm, Whatman International Ltd. (CAT#: STEM-L-5643-LC) Fluoropore Membrane Filter, 1.0 µm Pore size, Hydrophobic PTFE, 142 mm Membrane, Merck KGaA (CAT#: STEM-L-2756-LKN)