For safe transport. Waterproof, shatterproof, and dustproof. The automatic pressure equalization valve balances the pressure inside the case and prevents water from entering. O-ring seal. Open-cell core with a durable wall construction - robust and lightweight. Cubed foam in the bottom and convoluted foam in the lid. Ergonomic handle. The Peli 1150 plastic case offers optimal protection for sensitive equipment or tools. An O-ring seal and an automatic pressure equalization valve prevent dust and water from entering the interior of the plastic case.