10-Pack Changeable UID RFID Keyfobs 13.56MHz Smart Clone Cards
10-Pack Changeable UID RFID Keyfobs 13.56MHz Smart Clone Cards
10-Pack Changeable UID RFID Smart Keyfobs — 13.56MHz ISO14443A
Upgrade your access control setup with this set of 10 programmable UID RFID smart keyfobs. Compatible with the Mifare 1K S50 standard and operating at 13.56MHz, these cards allow you to freely rewrite Block 0 (the manufacturer/UID sector) to any UID value you choose — giving you full flexibility for cloning, testing, and custom access control deployments.
⚠️ Important Note: These cards require a dedicated 13.56MHz UID-compatible card writer. They are NOT compatible with NFC-enabled smartphones or the Mifare Classic Tool (MCT) app. Please ensure you have the correct writer hardware before purchasing.
Key Features
- Fully Rewritable Block 0: Modify the UID sector directly using a standard MIFARE read/write device — no special software required beyond your writer.
- Standard MIFARE 1K S50 Compatible: Functions identically to regular IC cards across all other sectors.
- ISO14443A Protocol: Industry-standard protocol for broad compatibility with 13.56MHz RFID readers and access control systems.
- Keyfob Form Factor: Compact and convenient — easy to attach to a keyring for everyday use.
- Waterproof Construction: Resistant to moisture for reliable performance indoors and outdoors.
- Wide Operating Temperature: Rated from -20°C to +55°C (-4°F to +131°F) for year-round reliability.
- Pack of 10: Ideal for system testing, multi-user deployments, or backup card creation.
Specifications
| Chip | UID (Block 0 Writable) |
| Protocol | ISO14443A |
| Frequency | 13.56MHz |
| Compatible Standard | MIFARE 1K S50 |
| Card Size | 85.5 × 54 × 0.8 mm |
| Working Temperature | -20°C to +55°C |
| Waterproof | Yes |
| Certification | CE |
| Model Number | UID-01A |
| Quantity | 10 pcs per pack |
| Country of Origin | Made in Mainland China |
Ideal Use Cases
- Access control system setup, cloning, and testing
- RFID development and prototyping projects
- Multi-user door entry deployments
- Backup card creation for existing 13.56MHz systems
Compatibility Reminder
These UID cards work exclusively with a dedicated 13.56MHz UID card writer/programmer. They will not respond to NFC write functions on mobile phones and are incompatible with Mifare Classic Tool (MCT). Please confirm your writer supports UID chip modification before use.
For background on RFID technology standards and security considerations, visit the NIST Cybersecurity Resource Center.
Frequently Asked Questions
Q: What equipment do I need to program these UID RFID keyfobs?
A: You need a dedicated 13.56MHz UID-compatible card writer/programmer (such as an ACR122U or similar UID-write-capable device). Standard NFC smartphone apps and the Mifare Classic Tool (MCT) are not compatible with these cards. Check that your writer explicitly supports UID chip Block 0 modification before ordering.
Q: Can I rewrite the UID on these cards multiple times?
A: Yes — that is the primary feature of these changeable UID cards. Block 0 (the manufacturer/serial number sector) can be overwritten multiple times using a compatible 13.56MHz UID writer, making them ideal for testing, cloning, and flexible access control configurations.
Q: Are these keyfobs waterproof and suitable for outdoor use?
A: Yes. These RFID keyfobs feature a waterproof design and are rated for operating temperatures from -20°C to +55°C, making them suitable for both indoor and outdoor access control applications in a variety of climates.
Q: What is the difference between these UID cards and standard MIFARE 1K S50 cards?
A: Standard MIFARE 1K S50 cards have a factory-locked Block 0 that cannot be changed. These UID variant cards function identically in every other respect, but allow Block 0 — which contains the card's unique identifier — to be freely reprogrammed, giving you control over the card's UID for cloning or custom access control purposes.