An RFID transponder or RFID label is the core element of any RFID system and enables the contactless identification of products, assets, or containers. It typically consists of a microchip and an antenna, integrated into a label, inlay, or robust tag housing. When an RFID reader emits radio frequency energy, the antenna of the transponder captures this energy and uses it to activate the chip. Passive RFID transponders, which are most commonly used in logistics and industrial applications, do not require a battery and are powered entirely by the reader’s electromagnetic field. How tag, reader and software work together as a whole is covered in the RFID technology basics.
Once activated, the transponder responds by transmitting its stored data—such as a unique ID or product-specific information—back to the reader using a process known as backscatter. This communication happens without line of sight and allows multiple RFID labels to be read simultaneously, even in motion. Depending on the RFID frequency (HF, NFC, or UHF), read ranges can vary from a few centimeters to several meters.
IDCRAFT supplies UHF | RAIN labels and hard tags as well as HF | NFC labels and cards, optimized for diverse materials, environments, and use cases. For custom-printed and encoded RFID labels and tags we run our own print and encoding service; for special housings we produce 3D-printed RFID transponders. Combined with the right RFID readers and system expertise, these solutions enable reliable identification, automation, and full transparency across the supply chain.
Which chip for which purpose?
HF and NFC at 13.56 MHz. NTAG213, 215 and 216 are the standard chips for NDEF content with 144, 504 and 888 bytes of user memory respectively — the choice for product information, authentication and smart packaging. ICODE SLIX and SLIX2 under ISO 15693 read several transponders at once and reach further than ISO 14443; they are the standard in libraries and industrial laundry. Access control and credentials typically use MIFARE families with cryptographic protection.
UHF and RAIN at 865 to 868 MHz in Europe. The governing standard is EPC Gen2v2 under ISO 18000-63. Common chips come from Impinj (M700 series), NXP (UCODE) and Alien. Memory is split into banks: the TID carries an immutable factory serial number, EPC memory holds the programmable identifier such as an SGTIN-96 built from GTIN and serial, and user memory is available for your own data.
The chip decides more than storage. It determines whether the tag can be locked, whether it can be cryptographically authenticated, whether it delivers sensor data, and how sensitive it is to metal and liquids. These questions belong at the start of a project, not at the end.
The form factors compared
- Card — HF and NFC, a few centimetres. ISO card format, printable. For access, time recording, employee badges and payment.
- Key fob and wristband — HF and NFC, a few centimetres. Rugged, on a keyring or wrist. For access, events and cashless payment.
- Label — mostly UHF, up to several metres. Thin, printable and encodable in the printer. For logistics, retail and inventory.
- Industrial and on-metal tag — UHF and HF, up to several metres depending on build. Resistant to metal, heat, chemicals and impact. For tools, containers, equipment and test gear.
Metal and liquids change behaviour far more than any datasheet figure suggests. A tag that reads eight metres in free air can drop to zero on a steel container. So the rule for every selection is: test it in the real mounting position, not on a desk.
Matching transponders from the portfolio
Cards: CT RFID Cards, the ACS PocketKey NFC Card with FIDO2 and ISO 14443 Type A, and the ACS ACOS5-EVO with ISO 7816 and cryptographic protection.
Key fobs: CT PVC Keyfob, CT ABS Keyfob and CT Epoxy Keyfob, each available with various HF | NFC chips.
Labels: the CT RFID Label with chips from Impinj, NXP or Alien, the CT ECO LABEL with 90 percent less plastic at the same performance, and the HID IQ Pro Label.
Industrial and on-metal: HID IQ On-Metal, Xerafy Metal Skin, the Xerafy Micro Tag for tight spaces and the CT Flag Tag for high-value items.
Custom form factors are made in house: the RFID 3D Tag is printed from PLA or ABS with either a UHF or an HF chip, and its shape and marking can be adapted freely.
Full lists are available under UHF | RAIN transponders and HF | NFC tags.
