News

Seals come in many forms... Pull-through Security Seals, Fixed-Length Security Seals, Security Padlock Seals, Barrier Seals (Cable Seals and Bolt Seals), Wire/Rope Meter Seals, and even Reuseable Electronic Seals. Security seals also include security tapes and labels, suitable for flat surfaces and edges on enclosures such as crates, cartons and pallets. Each type is designed for particular types of applications - for more information, see types of security seals.

Each security seal will have a particular tail or hasp diameter, an effective useable length, and a standard flag size for visibility of printed identification markings. Narrower seals are useful where seals must fit into smaller apertures, and for this many of our pull-through seals have smaller diameters, such as the MiniLock 570's 1.4mm tail thickness and UniTite 414's 2mm thickness. We also offer extra long seals, such as the UniStrap 412-XL (overall 51cm length) and UniTite 413 (overall 49cm length). In terms of flag size ("marking area"), we offer specialised security seals such as our UniFlag Security seal, which has a large format (108x56mm size). 

Common materials in use for security seals are polypropylene, nylon, aluminium and steel. Polypropylene is a popular choice for pull-through seals, as it offers a combination of strength, flexibility and wide operating temperatures. However, all types of plastic do become brittle at increasingly low temperatures, and do degrade when exposed to UV light, long-term saltwater exposure, solvents etc. Metal aluminium and galvanised steel cable seals provide more durability and strength where circumstances dictate, and we can also specify stainless steel cable grades for most demanding applications: see our Flexigrip 150M and Flexigrip 325M models.

Seals are specified for particular strengths – for certain applications such as fire extinguishers, kit bags and first aid trolleys it is desirable to have a very low break-strength so that seals can be broken in an emergency – for others, for example mail sack security seals, it is important that seals with strong break strengths are used so that bags do not burst open when under tension. There is a wide range of tensile strengths available, from 5KgF all the way up to 2000KgF, so understanding the possible forces relevant for your application is important for specifying the right kind of seal.

We categorise our security seals as having either a Low, Medium or High degree of tamper-evidence, based on design and construction features, method and material of construction, and level of certification.

Linked to the above, higher levels of security seals are often required for international freight movements - in particular, High Security Seals as classified under ISO17712:2013 regulations for international shipping container and freight movements.

Some applications require easy-access into a sealed enclosure, and for this we have security seals that can be removed easily by hand, either with low-break strengths (see our Fireseals) or tear-line features (see our Tracewaste Tear-Off and UniStrap 412LT).

For other requirements, security seals need to be robust and should not be removed intentionally without simple tools such as scissors or tin-snips, such as our UniTite 413.

In other scenarios, particular for barrier seals, we have our heavy-duty cable and bolt seals, products such as our Flexigrip 325M, Flexigrip 500M and Fork seals which necessitate the use of heavy-duty cutting tools like bolt croppers to remove.

Sustainability should of course be at the heart of every business, and security seals should be no exception. All of our plastic security seals are 100% recyclable, and we are increasing options for recycled content and biodegradable security seals on a regular basis.