Security Seals and Tamper-Evident Systems: a Practical Guide

Author: Marco Ghirardi – StickersTheb S.r.l.
Thest updated: 13 July 2026

security seals and tamper-evident systems make an opening, removal or unauthorised access visible. They can be used by private users, shops, laboratories, workshops, companies, warehouses, logistics operators, e-commerce businesses, administrators and plant managers.

The right choice depends on what you need to protect: a parcel, container, case, electronic device, technical door, meter, document or container may require different solutions.

Quick choice

For parcels and cartons, choose a VOD tape or a security bag; for warranties and devices, use VOD or ultra-destructible labels; for sacks, cabinets and containers, choose plastic seals; for doors, valves and technical access points, consider cable seals; for containers and critical transport, you may need bolt seals with SO 17712 documentation.

What does tamper-evident really mean?

A tamper-evident system, also called tamper-evident, does not necessarily make opening impossible. ts main purpose is to deter, identify or document an access attempt.

Deterrence

The presence of a seal makes it clear that the contents or device is under control.

Evidence of opening

Breakage, a VOD message, detachment or fragmentation show that the system is no longer intact.

dentification and traceability

Sequential numbering, barcodes, QR codes and internal records can link a seal to an order, parcel, vehicle, piece of equipment or operator.

mportant

A tamper-evident seal does not replace a lock, anti-theft device, alarm system or monitoring procedure. t should be considered a passive control measure, not an absolute guarantee against theft or unauthorised access.

Which solution should you choose for your application?

Application ndicative solution What to check
E-commerce cartons and parcels VOD tape or closure label Adhesion to the carton, width, visible message and quantity
Documents, keys and sensitive items Numbered or barcoded security bag Format, closure, receipt, numbering and opacity
Notebooks, smartphones, equipment and warranties VOD or ultra-destructible label Surface, desired residue, size and temperature
Sacks, boxes, cabinets, carts and containers Adjustable or fixed-length plastic seal Usable length, hole diameter, strength and numbering
Doors, valves, cages, tanks and technical access points Cable seal Cable diameter and length, material and removal tool
Containers and international transport Bolt seal SO 17712 documentation, numbering and carrier procedures
Water, gas and electricity meters Sealing wire, technical seal or magnetic influence indicator Compatibility with the installation, environment and inspection procedure

Main types of security seals and tamper-evident systems

1. Plastic seals

They are one of the most versatile solutions for sacks, containers, lockers, carts, cases, boxes and shipments. They can be adjustable, also known as pull-tight, or fixed-length.

Adjustable models let you tighten the seal to the desired position. Fixed-length models help standardise application. Sequential numbering and different colours make checks, inventory and identification easier.

View plastic seals

2. Cable seals

They use a metal cable that passes through one or more closing points. They are suitable for doors, valves, cages, tanks, vehicles, technical containers and applications where a standard plastic seal is not robust enough.

Before choosing, check the cable diameter and length, hole size, required strength and removal method. The strongest models may require bolt cutters or a suitable tool.

View cable seals

3. Bolt seals for containers

Bolt seals, also called pin or bar seals, generally consist of a pin and a single-use locking body. They are mainly used on containers, trailers and logistics closures that require a stronger mechanical barrier.

When a procedure requires compliance with SO 17712, it is not enough for a product to have the shape of a bolt seal: you must check that the specific model comes with the required documentation.

View bolt seals

4. VOD labels and tapes

When removed, they reveal a visible message or pattern such as VOD, OPENED or a security design. They are suitable for boxes, devices, doors, containers, documents, equipment and packaging.

Some versions transfer the message completely to the surface, others transfer it partially, while some leave no residue. The choice depends on how obvious removal must be and whether the support needs to remain clean.

To learn more about this technology, read our guide to tamper-evident labels .

View VOD labels and tapes

5. Ultra-destructible labels

They are made from materials designed to break into small fragments when removal is attempted. This makes it difficult to remove the label intact and reuse it on another object.

They are often used as warranty seals, for equipment identification, component control and protection of screws, panels or access points.

View ultra-destructible labels

6. Security bags

They are suitable for documents, keys, valuables, samples, returns, confidential correspondence and small items. They may include a VOD closure, sequential numbering, barcode, writable area and detachable receipt.

For business use, choose the right format and define who prepares the bag, records the number, receives it and handles any discrepancy.

View security bags

7. Tamper-evident systems for meters

Meters, valves, boxes and measuring devices may require sealing wire, rotary seals, protective covers or specific magnetic-influence indicators.

These are technical applications: choose the product according to the installation, environment, the procedure of the utility or administrator and the inspection method.

View meter security systems

Water, impact and tilt indicators: what is the difference?

A condition indicator does not perform exactly the same function as an opening seal. t detects a specific event, such as contact with liquid, an impact or tilting beyond a defined condition.

  • Water water indicators can signal contact with liquids on devices, components or equipment.
  • Water impact indicators help check whether a parcel has suffered a shock during transport.
  • Water tilt indicators can show that a package has been overturned or handled in an unexpected way.

These devices can complement a tamper-evident closure, but they should not be confused with a mechanical seal or VOD closure.

Solutions for private users

Private users can also use tamper-evident seals and labels when they want to check the integrity of an item or closure without installing complex systems.

  • Parcels, boxes and returns to be shipped.
  • Cases, lockers, boxes and small containers.
  • Notebooks, consoles, smartphones and devices sent for service.
  • Sports equipment, tools, spare parts and items to identify.
  • Documents, keys or small items kept in numbered bags.

For private use, a simple and immediately readable solution is often more useful than an overly robust or complex device.

Solutions for companies, logistics and e-commerce

n a company, a seal should not be treated as a simple product to apply: it should become part of a repeatable procedure. Numbering or a barcode is useful only if it is recorded and checked.

An effective business process may include:

  1. Assigning the seal to an order, parcel, vehicle or piece of equipment.
  2. Recording the serial number or barcode.
  3. Application by an identified operator.
  4. Taking a photograph of the seal and closing point when appropriate.
  5. Checking the number and integrity at delivery or inspection.
  6. Reporting discrepancies, breakage or anomalies.
  7. Retaining the data according to internal procedures.

This organisation is particularly useful for logistics, e-commerce returns, maintenance, asset control, laboratories, T, document transport, public administrations, condominium management and technical equipment.

How to choose the right seal

1. dentify the closing point

Check the hole diameter, distance between the points to connect, available space and any edges that could damage the seal.

2. Check the surface

For labels and tapes, distinguish between cardboard, plastic, metal, glass, painted, rough or porous surfaces. A solution that works on smooth metal may adhere poorly to recycled cardboard or low-surface-energy plastic.

3. Consider the environment

Temperature, humidity, UV rays, water, dust, vibration and outdoor exposure can affect adhesion and service life.

4. Decide what evidence you want

You can choose mechanical breakage, a VOD message, residue on the surface, label fragmentation or numbering to be checked.

5. Consider removal

A robust seal may require tools. A residue label may be suitable for packaging but not for a delicate surface or a device that must remain clean.

6. Define quantity and customisation

For business supplies, consider annual quantity, reorder frequency, colours, numbering, barcode, logo and dimensions. Customisation and minimum production quantities depend on the selected model.

Bolt seals and SO 17712

The SO 17712:2013 sets uniform procedures for classifying, accepting and controlling mechanical seals used on containers for goods transport.

The standard does not mean that every metal or bolt seal is automatically compliant. When compliance is required by a customer, carrier or international procedure, check the documentation for the specific model rather than relying only on the commercial title.

Even the best seal loses effectiveness if it is stored without control, applied incorrectly, recorded with the wrong number or accepted without checking it at delivery.

Errors to avoid

  • Choosing the strongest seal without checking that it fits the available hole.
  • Applying a label to dust, grease, silicone, moisture or an incompatible surface.
  • Using a residue-free label when you actually need a permanent trace.
  • Recording a shipment without noting the seal number.
  • Failing to define who is authorised to break or replace the seal.
  • Calling a product “SO 17712” without checking the model documentation.
  • Presenting a seal as an absolute guarantee against theft or tampering.

Frequently asked questions

Does a seal really prevent theft?

Not necessarily. t may deter, make access more difficult or show that a closure has been breached, but it does not replace an anti-theft system.

What is the difference between a VOD label with and without residue?

The transfer version leaves a message or pattern on the surface. The residue-free version shows opening on the label while keeping the support cleaner. Exact characteristics must be checked in the product sheet.

Can security seals be reused?

Most security seals are single-use. After breakage or removal, replace them with a new seal and, if possible, record the new number.

Which solution is best for a parcel?

On ordinary cardboard, VOD tape or a label on the opening point may be suitable. For documents or small sensitive items, a security bag may be more appropriate.

Which label should use on an electronic device?

t depends on the surface material and the desired effect. VOD labels are useful when you want to display an opening message; ultra-destructible labels when you want to make intact removal difficult.

Are all bolt seals compliant with SO 17712?

No. Compliance must refer to the specific model and be supported by the relevant documentation.

Can order customised security seals?

Some models may be available with numbering, colours, logo, text, barcode or custom formats. Feasibility and minimum quantity depend on the product and production process.

Find the right tamper-evident system

Browse the full range or go directly to the category closest to your application.

Business supplies

For quantities, recurring supplies, numbering, barcodes, colours, formats or customisation, send a request stating the application, surface, environment, expected quantity and desired result.

For a more precise assessment, it is also useful to attach a photo of the closing point or support where the product will be applied.

Request a business supply

Technical reference

This guide is for information only. Performance, compliance, strength, compatibility and use conditions must be checked in the product sheet and documentation for the specific product.