Spectrum Sterile PVDF Syringe Filters, Porosity 0.45 um, Diameter 13 mm - 100 ea. Specifications. 3603404: 882-66690: $258.70: PK: 882-66693: Spectrum Sterile PVDF Syringe Filters, Porosity 0.22 um, Diameter 25 mm - 100 ea. Specifications. 3603406: 882-66693: $304.30: PK: 882-66696: Spectrum Sterile PVDF Syringe Filters, Porosity 0.45 um