Has this parcel been opened? How a VOID seal gives it away

A taped box can be slit open and closed again with identical tape, and nobody notices until it is unpacked – if they notice at all. A security seal label is the simple fix: a label that cannot be peeled off and put back without leaving evidence.

How a seal label "breaks"

There are three types, often combined on one label.

VOID seals. They stick like an ordinary label, but if someone peels one off, part of the printed layer stays behind and the word VOID (or a chequerboard pattern) appears. Even if the label is pressed back down, the pattern stays visible.

Destructible seals. The face material is so brittle that it tears into small pieces when anyone tries to lift it. It cannot be removed in one piece.

Holograms. These don't show opening; they prove authenticity, because they are very hard to copy on a normal printer. They are added when counterfeiting is also a concern – see our hologram labels.

Placement: where a seal does its job

• Across the opening. Half on the flap, half on the side of the box. On equipment, across the seam between two housings or over a screw.
• Clean, dry surface. Dust and moisture stop the adhesive bonding properly, and then the VOID effect is weaker too.
• Give it time. Adhesive reaches full strength after a few hours. A seal applied a minute ago can sometimes come away cleanly.

Numbered seals

For cash bags, samples, warranty parts or high-value shipments, each seal carries a unique sequential number. Note it on the delivery paperwork and check it on arrival. An intact seal with the wrong number is just as much a warning sign as a broken one.

Where seal labels are used

• High-value e-commerce parcels (electronics, cosmetics, fragrance)
• Warranty seals on devices – the label over the case screw
• Food and supplements: proof that a jar or tub hasn't been opened
• Asset tags that shouldn't move from one laptop to another
• Doors, cabinets and meters that need sealing

Which one do you need?

For basic opening checks on cartons, a VOID seal is enough. If your product is often copied, add a hologram. If every shipment must be traceable, order them numbered. Our security labels come in all three versions, with your logo if you like, and our guide to VOID and hologram labels goes into the materials. For a custom run, use the quote form.