Syringe Filter: 25 mm Membrane Dia., 0.45 um Pore Size, Nylon, 100 PK. Item # 12K961. Mfr. Model # 12K961. UNSPSC # 41104922. Catalog Page # 662. Country of Origin USA. Country of Origin is subject to change. Lab Safety Supply disposable, nonsterile nylon/polyamide filtration media syringe filters feature Luer-Lok™ and pressure fittings.