What are Container Seals?

Container  seals are a strong locking device used to seal and secure international cargo containers once shipment is loaded. Upon placing a container seal, a container has been properly closed at origin. Because these seals can only be removed once, it ensures that a container remains unopened during the journey to its final destination where it is removed by the consignee.

These metal container seals therefore provide tamper evidence and help to detect cargo theft or contamination. These security seals have a relative high breaking strength and therefore also provide a greater level of security than most other security seals. A container seal has its own unique number as identification and this number is listed on the shipping paperwork. The people receiving the container must check the bill of lading and check whether the seal number matches with the number on the container.

A container bolt seal used for securing containers must conform to the ISO 17712:2013 high security seal standard in order to be accepted by customs all around the world in ocean shipping. ISO 17712:2013 certified bolt seals comply with CTPAT as well. CTPAT, which stands for Customs Trade Partnership Against Terrorism, was started by U.S. Customs and Border Protection to strengthen international supply chains and improve United States border security.

Container Seal Options

Container seals come in many different shape, size and security levels. We offer a range of high-security, ISO 17712 compliant security seals for use when transporting cargo by land, sea or air. Below are only a few of our most popular container seals:

HMRC Bolt Seals

The plastic coated bolt and locking bush are moulded as a unit and laser marked with identical sequential numbers for added security. The seals are packed in high quality clear re-closable wallets of ten seals, making it easy to remove seals singularly and then re-close the wallet. When the seal has been locked the bolt spins freely on the locking bush to confirm seal integrity. The seal can only be removed using bolt croppers. The Acme Bolt Seal is an ISO 17712:2013 (E) compliant high security bolt seal, designed for high value ISO container cargo shipments. You can purchase this seal by visiting our product page HM Revenue and Customs Bolt Seal (£57.50 per 100).

Metal Cable Seals

Cable Seals are classed as a barrier seal, which is a variable length cable security seal, and provides a high level of security through its unique locking mechanism and cable design. High security Cable Seal are easily applied by hand and can be used to secure trucks, shipping containers, tankers, railcars, valves. Once closed or cut it cannot be resealed. This seal has successfully passed the stringent ISO PAS 17712:2013 test. You can find this product by visiting our product page Metal Cable Seals (£60.00 per 100)


The Forkseal provides complete wrap-around protection of container locking bars of any size and offers the highest form of container security. The seal plates and bolt seal can be fitted at an appropriate section of the fork. The seal provides a high-level of physical strength – the strong steel can only be cut at the designated cutting point. The seal resists manipulation and substitution with numbering replicated on the pin and fork bar. The Forkseal safety locking system protects container doors, railway cars, truck trailers, international freight and more. This seal is approved by both UK and US customs as is fully compliant with ISO 17712:2013 HSS (high security seal) WITH ISO/IEC 17025:2005. You can purchase this seal by visiting our product page Forkseal (price based on quantity).


The Metal Ballseal are extremely durable, providing secure protection for shipments in transit.  It is a reliable and acts predominantly as an immediate indicator that goods have been received as sent. The seal features a locking mechanism totally enclosed in the head, which is secured by two independent spring rings. Once the two spring rings click shut the Globe Seal cannot be resealed. The seal is applied without the need of tools and is fully compliant with ISO PAS 17712. You can purchase this seal by visiting our product page Metal Ballseal (£80.00 per 1,000).


ISO 17712 Security Seals

This ISO standard documents uniform procedures for the classification, acceptance and withdrawal of mechanical freight container seals. ISO 17712 defines 3 types of classes of security seal strength: “I” for indicative, “S” for security and “H” for high security, where H has the highest strength, also known as barrier capacity.

Security seals has to be tested by an independent third party laboratory to validate the security seal’s classification. The test laboratory must be accredited according to ISO 17025 for testing specific to ISO 17712.

The ISO 17712 standard requires independent testing against three main categories:

  1. Security seals must be tested to determine its physical strength.
  2. Seals must be designed and constructed with tamper indicative features that generate tell-tale evidence of tampering.
  3. Manufacturer’s security-related business processes must be audited.

More information and details about ISO 17712 can be found in ISO’s official documentation.

CPAT Regulation

Under the Customs Trade Partnership Against Terrorism (CTPAT) full Instruments of International Traffic (i.e. shipping containers) must have high security seals properly affixed at the point of stuffing to prevent pilferage, terrorist devices, and other contraband from entering the global supply chain.

Customs Trade Partnership Against Terrorism (CTPAT) is but one layer in U.S. Customs and Border Protection’s (CBP) multi-layered cargo enforcement strategy. Through this program, CBP works with the trade community to strengthen international supply chains and improve United States border security. CTPAT is a voluntary public-private sector partnership program which recognizes that CBP can provide the highest level of cargo security only through close cooperation with the principle stakeholders of the international supply chain such as importers, carriers, consolidators, licensed customs brokers, and manufacturers.

CTPAT requires the use of ISO 17712 “H” class seals. Our high security seals are all C-TPAT compliant. You can find these products by visiting our Metal Security Seals.

Global Shipping Standards

An ISO 17712 compliant seal should be applied at all times during the transport under and that all the letters and digits of the HSS number shall be manifested properly and accurately on the Shipping Instructions, Bill of Lading, Manifest, or any other documentation related to the movement of the cargo. All shipments transported that are capable of being sealed must be secured immediately after loading/stuffing/packing by the responsible party (i.e. the shipper or packer acting on the shipper’s behalf) with a high security seal that meets or exceeds the most current ISO 17712 standard for high security seals and emphasised on a contract of carriage (Bill of Lading) which states under section 11.3:
The Merchant is responsible for the packing and sealing of all Merchant-packed Containers and, if a Merchant-packed Container is delivered by the Carrier with an original seal as affixed by the Merchant or customs or security control intact, or the Carrier can establish bona fide circumstances in which the original seal was replaced, the Carrier shall not be liable for any shortage of Goods ascertained upon delivery.

As a best practice, it is recommended Shippers take clear photographs of the following when preparing shipments for transit:
1. Their shipments inside the container before closing the doors;
2. The both container doors in the closed position indicating the container number;
3. A legible close-up of the seal and the seal number before affixing it to the container; and lastly,
4. Seal properly affixed to the right door locking rod or lower right locking rod cam.

Brexit and Border Guidelines

In an ever-looming Brexit world, new custom policies and regulation still remain a mystery to many within the transport industry. However, one thing is for certain – regulation and administration requirements will increase, as goods like medicine and food will need to be stringently secured and accounted for throughout the entire journey. However Regulation 952/13 has introduced the requirement that, for containerised transports, seals with high-security features are shall be used to the widest possible extent. Below are guidelines and regulatory standards that have been supplied by HMRC for those looking to import and export goods across the border after Brexit.

UK seal standards

The types of trader seal that HMRC will accept for control purposes fall into the following categories:

  • Seals that can withstand a force of 1,000kg (security seals) – HMRC GROUP 1 BARRIER SEALS (H)
  • Seals that can withstand a force of 250kg (indicative seals) – HMRC GROUP 2 BARRIER SEALS (S)
  • Other acceptable seals –  HMRC GROUP 3 BARRIER SEALS (I)
  • Bar box group – Seals used to secure aircraft bar boxes

Seal characteristics

The seals must:

  • remain intact and securely fastened in normal use
  • be easy to check and recognise
  • be manufactured so that any breakage or removal leaves traces visible to the naked eye
  • be designed for single use, or if intended for multiple use, be so designed that they can be given a clear, individual identification mark each time they are re-used
  • bear an individual identification mark, on the basis of which customs can identify the person concerned – the mark must be uniquely numbered

Seal specification

The seals should have the following specifications:

  • form and dimensions of the seals can vary depending on the method of sealing used but the dimensions must be such as to ensure that identification marks are easy to read
  • identification marks of seals must be impossible to falsify and difficult to reproduce
  • material used must be resistant to accidental breakage and prevent undetectable falsification or re-use

Conditions of Acceptable Seals

Acceptable seals  must meet the following conditions:

Number Condition
1 Your seals must each bear a permanent unique identifying mark, be serially numbered and used in sequence
2 You must keep all seals and sealing equipment under lock, with the key being held by a responsible person of your company
3 You must keep a permanent stock record showing the receipt, serial numbers, use and disposal of seals, which must be produced to a customs officer on request
4 You must regularly inspect and balance your seal stocks to guard against interference or substitution
5 All defective seals, and seals you remove after use, must be kept available for inspection by customs, with whom you must agree a method for their disposal
6 The marks and numbers of the seals used must be clearly shown on documents accompanying the goods
7 Seals may be applied or removed only by you or by responsible employees authorised by you to act for you


You can purchase our ISO17712:2013 (E) compliant HMRC Bolt Seals by clicking below:

You can purchase our ISO17712:2013 (H) compliant Metal Wire Cable Seals by clicking below:

You can purchase our ISO17712:2013 (I) compliant Ball Seals by clicking below:

You can purchase our ISO17712:2013 (H) compliantHeavy-Duty Fork Seal by clicking below:

If you require a more bespoke option, you can use contact us by visiting the quote page here or alternatively you can call our sales team on +44 1252624305.

About JW Products

JW Products
manufacture security seals and clinical waste ties from our purpose built factory in St Helens, producing high-quality, fully customisable security seals, including bolt seals, container seals, and trailer seals, across a wide range of industries. Through investment in both innovative manufacturing and quality customer service, JW has been producing high-quality seals for over 20 years. The company conforms to the highest standards of ISO-9001:2015 and supplies both public and private sectors, including the NHS and Greater Manchester Police.