Double wall exterior with 1 1/2" of insulating air space. Internal self-closing lid has locking Sure-Grip™ handle. Combo unit has two internalcompartments: a double wall safety area and a larger general storage area. Protected by a superior powder coat paint with UV protection to stand up to outside elements. Cover support is welded to reinforcing channels for extra strength. Recessed handles on sides and lid eliminate any protrusions that could be damaged during transport. Heavy-duty runners allow easy fork lifting. Extra thick tang is welded to lid and securely interlocks with padlock (padlock not included). Optional casters can be attached for mobility