Watertight, crushproof, and dustproof. Features a watertight silicone O-ring lid. Open cell core with solid wall design - strong, lightweight. Over-molded rubber, top and side handles for a comfortable grip. Retractable extension handle when transporting your valuables. Opens easily with double throw latches. Stainless steel hardware and padlock protectors. Automatic Pressure Equalization Valve - balances interior pressure, keeps water out. 2 strong polyurethane wheels with stainless steel bearings.