Medical Millex-HP Syringe Filter Unit, 0.45 µm, polyethersulfone, 33 mm, sterilized by gamma irradiation. 1 Product Result. | Match Criteria: Product Name, Description. SLHPM33RS. A 33 mm diameter sterile syringe filter with a 0.45 µm pore size hydrophilic Polyethersulfone (PES) membrane. Comes in