This sterile plastic funnel reduces operation time in colony and particle analysis. For use with Sartorius membrane filters and Sartorius cardboard culture plates. Note: BioSart® 250 funnels can also be adapted to fit single filter holders or filtration manifolds. This sterile plastic funnel reduces operation time in colony and particle analysis. For use with Sartorius membrane filters and Sartorius cardboard culture plates. Note: BioSart® 250 funnels can also be adapted to fit single filter holders or filtration manifolds.