Container seal tags are the container lock, but can only be used once to open, it can not be used again after it broke. Above the tags have a title which is unique, if the container seals customers get are the same number with the bill of lading, it is behalf of the container is not open, the cargo intact. It is not marks, marks refers to goods packaging and printing mark, is not the same thing.

Seal tagscan be divided into: High security seal, digital burglar seal, bullet seal, iron seal, wire seal, plastic seal, security seals, common seals.

An intermodal container (also container, freight container, ISO container, shipping container, hi-cube container, box, conex box and sea can) is a standardized reusable steel box used for the safe, efficient and secure storage and movement of materials and products within a global containerized intermodal freight transport system. "Intermodal" indicates that the container can be moved from one mode of transport to another (from ship, to rail, to truck) without unloading and reloading the contents of the container.

The standardised steel shipping container has its origins in the 1950s when commercial shipping operators and the US military started developing such units. The logistics method employing these was named Container Express and was abbreviated ConEx. That abbreviation evolved into a word within the American English lexicon.

The seal tags often imposed by a particular person, after stowing the container and close the door properly, it is similar to the device like lock. Customs seals of seals according to staff applied can be divided into commodity inspection seal, seal enterprise knowledge and commercial or seals. Customs unpacking inspection, Customs will usually be applied to plastic seals.

Shipping company seals printed Carrier's name (abbreviated as COSCO, MSC, PIL) and a series of Arabic numerals.