Padded removable sleeve for 15-17' laptop computers Watertight, crushproof, and dustproof Three removable accessory pouches Strong polyurethane wheels with stainless steel bearings Open cell core with solid wall design - strong, light weight Retractable extension trolley handle Easy open double-throw latches Comfortable rubber over-molded top and side handles O-ring seal Automatic pressure equalization valve - balances interior pressure, keeps water out