In the existing cargo box cover, scattering dust or uncaptured dust hampers the atmospheric environment. Rocks, nails, screws, etc. fall down from an imperfectly-covered cargo boxes, causing vehicle damages, and potentially subsequent vehicle traffic disasters. Preparation of safety measures was urgent due to human injuries and property damages caused by steadily-increasing fall accidents from freight vehicle's cargo. For improvements of such problems, Seonkwang Korea Co., Ltd. has developed a perfectly-sealed and automated system by supplementing the trap system. It is a completely-automatic method wherein the cover installed in the upper part of the cargo box moves while sliding backward when the control switch button is pushed, and is stopped by the stopper to perfectly cover up the rear face. It is a cover sealed by covering the whole upper part of the cargo box using a material with waterproof functionality and tensile strength of more than 500N so as to be able to prevent outflow of wastes or leakage of odors. In addition, customized production is possible in terms of sizes and types, etc. of the cargo box according to customer requirements.