Medical Millex-GV Syringe Filter Unit, 0.22 µm, PVDF, 33 mm, gamma sterilized. A 33 mm diameter sterile syringe filter with a 0.22 µm pore size hydrophilic PVDF membrane. Comes in a pack of 50. A 13 mm diameter sterile syringe filter with a 0.45 µm pore size hydrophilic PVDF membrane. Comes in a pack of 100.