As authentication NFC tags continue to grow, RFID TAG MAKER provides NTAG424 Tamper Tags. By combining the anti-counterfeit-certified NFC tag feature with tamper detection, brand owners can enhance the protection of their products. The authentication feature ensures that the NTAG424 Tamper Tags cannot be copied digitally, while the tampering feature prevents the tag from being physically moved.
What is the NTAG424TT tamper-proof loop label?
NTAG424TT Tamper Loop Tags have an additional wire loop in addition to the antenna loop. This loop is connected to the NFC chip on the NFC tag, which can be scanned to detect if this loop has been disconnected.
When the NTAG424TT tag is encoded, we also enable the TT feature by adding a special “tamper” code and configuring the chip to allow the tamper code to be displayed in the scan URL. For example, your standard URL might be.
If the NFC chip detects that the loop has been broken, the chip can change the URL at scan time by changing the tamper code to the code used during encoding. For example, the URL would change to
When this is done, the server can check if the tampering loop has been corrupted.
This type of NFC tag is used to monitor the opening of bottles, boxes, etc. The opening action breaks the loop. The key point here is that the tag will still scan even though the loop has been broken.
It is not the easiest product to use. You need to deploy the label in such a way that the tamper-evident loop is sure to break at the open bottle, etc. – but otherwise cannot be carefully removed. Labels are often made with small cuts in the “arms” to ensure that the tamper-evident loop is broken. Therefore, labels are usually designed specifically for certain bottles/packages and then carefully applied to avoid any potential alignment issues.
While the usual use case for tamper-evident loops is to detect open or broken seals, tamper-evident loops can also be used for more general purposes, such as jewelry labels. Unlike NFC antenna designs that require very careful design and alignment to scan correctly, a tamper-proof loop design is essentially just a wire loop with a more flexible design.
As a result, loops can be used for designs where interruptions can be more common, such as jewelry tag designs. The tag will continue to work after the loop is interrupted.
These are often very versatile designs that can reduce costs and speed deployment.
Tampering to destroy NFC tags
These tags are designed to be destroyed when tampered with and the scan will no longer be valid. They are easier to use and more versatile, and we are starting to stock these for testing and immediate use. These tags come in two types.
“Scratch tamper” labels (also known as fragile antenna labels) are designed to break down when tampered with. The surface material will crumble, and doing so will damage the antenna. Scratch-tamper labels are very effective and very thin, so they can be used under other labels. Ideal for use with wine bottles, for example where a design label can be placed on top.
Peel Tamper NFC tag
Peel tamper NFC TAG have two layers of material. The antenna is designed in such a way that when the top layer of material is removed – by trying to remove the sticker – then the antenna breaks off and the label will no longer function. These tags tend to be slightly thicker and work better as “stand-alone” tags.
In general, we prefer Tamper Destruct NFC tags. They are reliable to use, easier to apply and work as expected in most cases. The downside is that the tag can no longer be scanned after tampering, but in most use cases this is not a priority.
NTAG223 Capacitive tampering
NXP’s next-generation authentication NFC chips – NTAG223 and NTAG224 – include a new “state detection” tampering feature. This advanced technology will allow tampering to be detected using changes in capacitance rather than actual physical damage. This will allow for a more sensitive and potentially more reliable detection method.
In effect, it is a system between a tamper-cycling tag and a tamper-damaging tag. The tag would be able to detect the change but still function, but importantly be able to detect the change without causing any physical damage to the NFC tag itself.