Designed for particulate or biological contamination analysis of small volumes using a vacuum filter. Includes a stainless steel screen filter support and No. 5 perforated silicone stopper for easy attachment to a vacuum filtering flask. Membrane filters are not included. Thick prefilters or laminated filters will not seal in this holder, and it is not autoclavable with membrane filters installed. Unlaminated PTFE or PVDF membranes are recommended for solvent applications. Complete set includes a borosilicate glass funnel and base, removable stainless steel screen filter support, anodized aluminum spring clamp, and silicone stopper. Parts are also available separately.