Retractable extension handle, strong polyurethane wheels with stainless steel bearings, easy open Double Throw latches, open cell core with solid wall design – strong, light weight, O-ring seal, Automatic Pressure Equalization Valve, fold down handles, stainless steel hardware and padlock protectors, 4 level Pick N Pluck™ with convoluted lid foam, special foam inlets for O2k.