25MM MCE Black Grid Filter 1.2µm | Zefon International
10-Inch Sediment, Carbon Plus Chloramine, Mixed-Bed Color Changing Dei – aquaticlife.com
Kinesis KX Membrane Filter, PTFE, 13 mm dia., 0.22 µm; 100/pk from Cole-Parmer
Sartorius 11404-47N Membrane Filter Disc, Cellulose Nitrate, Non-Sterile, 0.8 μm, 47 mm, White with Black Grids (Pack of 100): Amazon.com: Industrial & Scientific