MicroFunnel Plus Disposable Filter Funnel Sterile 100mL. Gridded 0.45um Metricel Black modified polyethersulfone membrane for sampling ambient purified water systems. Leakproof vented lid and integral membrane seal. Filtration area: 13.46cm2. 635mm Hg vacuum. 6.1dia.x7.6Hcm (with cover).