Whatman membrane filters nylon pore size 0.45 um, diam. 47 mm- pkg of 100 ea Whatman filter
Merck Medical Millex™-HP Syringe Filter Unit, 0.45 μm Medical Millex-HP Syringe Filter Unit, 0.45 μm, polyethersulfone, 33 mm, sterilized by gamma irradiation Non-Sterile Syringe and Syringeless Filters | Fisher Scientific