Bolt seals gained popularity as a cheap and strong container seal option, and while their vulnerabilities were exposed 20+ years ago, they continue to be prevalent in the industry.

Here are the reasons we believe cable seals are superior from a security perspective.

1. Interchangeable Parts: bolt seals have no standard for design, but because most of them are hat and pin, 90% are interchangeable. Tamperers can come prepared with duplicate parts.
2. Duplicate Numbering: Most bolt seals are produced in Chinese factories that will print any seal number given to them by a company or individual. That means that there can be duplicate seal numbers from different companies, and tamperers embedded within the company can request and prepare duplicate bolts in advance just based on the subsequent numbers in a box. The bill of lading doesn’t specify if the bolt number should be on the hat and pin, just the hat, or what color the bolt should be for an upcoming shipment. We have witnessed several instances where containers with bolt seals were breached, and an extra seal was waiting inside the door to replace the tampered one.
3. Easily Tampered: Bolts can be spun to release the pin from the hat. They can be cut and re-threaded, and they can be cut and re-glued using highly accessible and robust materials. The strength of the steel doesn’t serve as a true protection.
4. No Tamper Evidence: There is no way to check for tampering. Square bolts or un-spinnable bolts can be cut and re-glued, and security personnel cannot discern if a bolt is un-spinnable or tampered and glued back together.
5. Don’t Secure Two-Bar Containers: When a bolt is applied to the right door latch on a two-bar container (essentially a container with parallel bars – one or two on each door), the bolt must be applied to the latch on one side. The rivet securing the latch to the bar can be removed, the door opened, and the rivet secured back into place undetected. You’ll often even see a rivet replaced with a nut to make it easier to remove. However, a secure cable seal with a 1500mm cable can provide a more reliable solution for securing the bars of both left and right container doors without the risk of tampering.

Why choose cable seals?

No standard exists for producing, numbering, or verifying bolt seals, so parts get replaced frequently without leaving any signs of tampering.

Unspinnable bolts were introduced to the market as a more secure option. However, they can be difficult to distinguish from bolts cut, threaded, or glued back together, confusing security personnel working with multiple bolt seal styles. As a result, instead of checking for tampering, personnel often cut the bolt at the destination and move on.

We design our seals to resist all five common forms of tampering. Redflag seals cannot be easily or quickly duplicated in China and work on all types of containers. Our product range provides varying levels of oversight and security, allowing you to select the appropriate level of protection for your shipment and identify any vulnerabilities in your supply chain.