Self-contained system minimizes user contamination Features a protective spork/filtration cap designed for optimal positioning within the collection vial Protective cap can only be removed from the collection vial with a provided key Adaptable cap accepts either a 15mL or 50mL conical centrifuge/processing tube Squeezable collection vial expedites specimen filtration Supplied as one- or two-vial kits which contain vials of specific fixatives/preservatives or clean vials Two vials of surfactant included with each case For fixative descriptions, see Para-Pak Parasitology Transport Systems