13.56MHz 125kHz RFID Readers
L210-U 125kHz USB Stick RFID Reader, Plug-In EM4100 Dongle
The L210-U is a 125 kHz RFID reader in a USB flash-drive format, 75 × 21 × 7 mm and about 10 g, for laptops, shared workstations and mobile staff. It plugs straight into a USB-A port, reads EM4100 and TK4100 cards and fobs at up to 80 mm, and types a 10-digit decimal number with no driver or cable.
- Frequency
- 125 kHz
- Cards / tags
- EM4100, TK4100, SMC4001 and EM4100-compatible cards and key fobs
- Interface
- USB-A plug (direct plug-in), keyboard emulation
- Output
- 10-digit decimal card number
- Read range
- Up to 80 mm (depends on card and environment)
- ✓ Sample units for evaluation
- ✓ Output format confirmed for your software
- ✓ Private label & OEM options
- ✓ Reply within 1 business day
Why integrators choose the L210-U
- No cable — plugs directly into a USB-A port, like a flash drive.
- Pocket size — 75 × 21 × 7 mm and about 10 g, with a key ring.
- Keyboard output — types a 10-digit decimal card number at the cursor, with no driver.
- Up to 80 mm range — EM4100, TK4100 and SMC4001 cards and fobs, read in under 200 ms.
- Low power — 5 V DC at 100 mA from the host port.
- Android through OTG — types into Android apps via a USB OTG adapter on devices that support it.
Where a stick reader beats a desktop pad
A desktop pad needs desk space and a cable run. The L210-U needs neither: it sits in the USB-A port and travels on a key ring between sites. It suits laptop-based card enrollment, hot desks and shared workstations, installers checking fob numbers on site, and compact POS terminals with no room for a pad.
Because the reader sits at the port, present the card close to the side of the laptop or terminal where it is plugged in. On a desktop PC with rear USB ports, a pad such as the L120-U is easier for users to reach.
The default output is a 10-digit decimal card number, and a custom format can be set on request. An LED and buzzer confirm each read; the read interval is under 0.5 s. Power comes from the port itself: 5 V DC at 100 mA.
Using the L210-U with Android devices
Android is on the supported list. Connect the stick through a USB OTG adapter, open the app and tap into the input field; the card number is typed as if from a keyboard. The phone or tablet must support USB OTG, so check this on the actual device model before a rollout.
For a direct plug without an adapter, the L220-C has a USB-C connector. The Android OTG checklist lists what to verify first, and the keyboard-emulation readers page shows every model that types into apps this way.
L210-U specifications
| Model | L210-U |
|---|---|
| Frequency | 125 kHz |
| Form factor | USB stick reader with key ring |
| Housing | ABS |
| Supported cards | EM4100, TK4100, SMC4001 and EM4100-compatible cards and key fobs |
|---|---|
| Card operation | Read-only (card ID number) |
| Read range | Up to 80 mm (depends on card and environment) |
| Read time | < 200 ms |
| Read interval | < 0.5 s |
| Interface | USB-A plug (direct plug-in), keyboard emulation |
|---|---|
| Driver | Not required |
| Default output | 10-digit decimal card number |
| Output options | Custom output format on request |
| Operating systems | Windows XP / Vista / 7 / 10, Linux, Android (USB OTG) |
| Indicators | LED and buzzer |
| Dimensions | 75 × 21 × 7 mm |
|---|---|
| Weight | Approx. 10 g (approx. 40 g packed) |
| Power supply | 5 V DC, 100 mA (USB) |
| Operating temperature | -10 °C to +70 °C |
| Storage temperature | -20 °C to +80 °C |
| Humidity | < 90 % RH |
Specifications of L210-U as supplied for the standard version. Read range depends on the card or tag, mounting surface and environment — we can test your own cards before you order.
Card, tag and system compatibility
Works with
- ✓EM4100, TK4100 and SMC4001 125 kHz cards and key fobs
- ✓Windows XP, Vista, 7 and 10, and Linux
- ✓Android phones and tablets with USB OTG support, via an OTG adapter
Card not listed? Send us the card type or a photo and we will confirm compatibility before you buy.
Integration in 4 steps
- 1
Plug the L210-U into a USB-A port, or into an Android device through a USB OTG adapter. It is detected as a keyboard.
- 2
Click or tap into the field that should receive the card number.
- 3
Hold the card or fob next to the stick: the buzzer and LED confirm the read and the 10-digit number is typed.
- 4
If your software expects a different number format, tell us before ordering; custom formats are set before shipment and confirmed on a sample.
OEM / ODM options for L210-U
- ◆Card-number output format set on request
- ◆Printed marking on the stick (your logo in place of the standard print) — confirmed in your quotation
- ◆13.56 MHz stick version for MIFARE cards (H210-U)
- ◆Private-label packaging — scope confirmed in your quotation
Typical applications
L210-U FAQ
Does the L210-U work with Android phones?
Yes, on devices with USB OTG support. Connect it through a USB OTG adapter and the card number is typed into the active field. For a direct USB-C plug, use the L220-C.
How much power does the L210-U draw?
5 V DC at 100 mA, supplied by the USB port. No external power is needed.
Does the L210-U need a driver on Windows or Linux?
No. It enumerates as a USB keyboard on Windows XP, Vista, 7 and 10 and on Linux, and types the 10-digit card number at the cursor.
How close must the card be to the L210-U?
Up to 80 mm, depending on the card or fob and the surroundings. Because the reader sits in the USB port, hold the card next to that side of the device.
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125kHz Tell us your card, interface and quantity
Send the card or tag type, the host system and your volume. We reply within 1 business day with a suggested model and sample options.