The Pelican 1660NF Case Without Foam is an unbreakable, watertight, airtight, dustproof, chemical resistant and corrosion proof hard case that can be used to carry any kind of equipment that needs to be protected from the elements. It is made of Ultra High Impact structural copolymer that makes it strong and durable. It has a 0.25 (6.4 mm) neoprene O-ring, ABS latches that seal perfectly and an automatic purge valve for quick equalization after changes in atmospheric pressure.