The closed concentration system allows for increased safety with a minimum of handling and odor. The 0.6mm holes in the filter allows the parasites to pass through, but block larger fecal material. Available in 15ml tubes or 50ml (holds 30ml) tubes. Each package includes a pre-assembled tube-strainer unit, Fecal Mucolytic reagent, dispensing spoons (for 15ml tubes), processing trays, and applicator sticks. Pictured with Scientific Device Laboratory’s environmentally- safe, formalin-free fixative Parasafe .