Capsules feature sturdy PP housings with fused seals—no glues or adhesives to contaminate filtrate. Capsules include a lure lock vent to guarantee that no filtration area is wasted. Use vent to draw solution into the capsule or let air escape from the capsule or sample port. Use polypropylene (PP) membrane filters for solvents, clean air/gas, prefiltration, and sample preparation Autoclavable.