Acrodisc Syringe Filter, 0.2 µm, wwPTFE membrane Minispike outlet, 13 mm (300/pkg) 4556. Acrodisc Syringe Filter, 0.45 µm, GHP Membrane, Minispike outletspike outlet, 13 mm (100/pkg, 300/cs) 2402. Acrodisc Syringe Filter, 0.45 µm, wwPTFE membrane Minispike outlet, 13 mm (300/pkg) 4558.