> For the complete documentation index, see [llms.txt](https://developer.magtek.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.magtek.com/products/dynafamily-mms-dyna-devices/dynaflex-ii-go.md).

# DynaFlex II Go

The DynaFlex II Go is a portable secure card reader authenticator (SCRA) that\
reads contact chip, contactless (NFC), and magnetic-stripe cards in a compact,\
handheld device. It encrypts cardholder data at the point of read (SRED) and\
connects over USB or Bluetooth LE — suited to both mobile and countertop\
acceptance. It uses the shared Dyna-family MMS command set, so everything you\
build against it is documented in the [<mark style="color:red;">**API & Command Reference**</mark>](https://developer.magtek.com/api-and-command-reference) and linked below.

### Key Capabilities

* **Contact, contactless (NFC), and magnetic stripe** card reading in one device
* **SRED** point-to-point encryption at the moment of read (TDES / AES DUKPT)
* **NFC/MIFARE** pass-through and NFC card emulation (DynaCast)
* **Optional barcode reader** (BCR) for scanning outside a transaction
* **Portable and battery-powered**, with status LEDs and a buzzer for prompts
* **PCI PTS POI**–approved SCRA (no PIN entry — see the DynaFlex II PED for PIN)

### How it Connects

<table data-header-hidden><thead><tr><th valign="middle"></th><th></th></tr></thead><tbody><tr><td valign="middle"><strong>Reference Section</strong></td><td><strong>Information Available</strong></td></tr><tr><td valign="middle"><a href="/products/dynafamily-mms-dyna-devices/dynaflex-ii-go/quickstart.md"><mark style="color:red;"><strong>Quickstart</strong></mark></a></td><td>The Go connects to a host over USB or Bluetooth LE. For wiring, pairing, and a first end-to-end transaction, start with the Quickstart.</td></tr></tbody></table>

### Build with the DynaFlex II Go

<table data-header-hidden><thead><tr><th valign="middle"></th><th></th></tr></thead><tbody><tr><td valign="middle"><strong>Reference Section</strong></td><td><strong>Information Available</strong></td></tr><tr><td valign="middle"><a href="/products/dynafamily-mms-dyna-devices/dynaflex-ii-go/programmers-manual.md"><mark style="color:red;"><strong>Programmer's Manual</strong></mark></a></td><td>The MMS command set scoped to<br>the Go: message format, commands, notifications, configuration, and status codes.</td></tr><tr><td valign="middle"><a href="/products/dynafamily-mms-dyna-devices/dynaflex-ii-go/programmers-manual/commands.md"><mark style="color:red;"><strong>Commands</strong></mark></a></td><td>The commands the Go supports, each<br>linking into the shared reference.</td></tr><tr><td valign="middle"><a href="https://developer.magtek.com/api-and-command-reference/dynafamily-command-matrix"><mark style="color:red;"><strong>Command Support Across Products</strong></mark></a></td><td>The full device Command matrix, if you're building for more than one Dyna reader.</td></tr><tr><td valign="middle"><a href="/products/dynafamily-mms-dyna-devices/dynaflex-ii-go/security-and-keys.md"><mark style="color:red;"><strong>Security &#x26; Keys</strong></mark></a></td><td>DUKPT (3DES→AES),<br>MAC, KSNs, encryption/decryption, and PCI requirements.</td></tr><tr><td valign="middle"><a href="/products/dynafamily-mms-dyna-devices/dynaflex-ii-go/nfc-mifare.md"><mark style="color:red;"><strong>NFC/MIFARE</strong></mark></a></td><td>Working with contactless cards and tags <br>(NTag, Classic, DESFire, Plus).</td></tr><tr><td valign="middle"><a href="/products/dynafamily-mms-dyna-devices/dynaflex-ii-go/documentation.md"><mark style="color:red;"><strong>Documentation</strong></mark></a></td><td>Essential documentation resources for developing with and managing the DynaFlex II Go secure card reader.</td></tr></tbody></table>

### Downloads & Compliance

<table data-header-hidden><thead><tr><th valign="middle"></th><th></th></tr></thead><tbody><tr><td valign="middle"><strong>Reference Section</strong></td><td><strong>Information Available</strong></td></tr><tr><td valign="middle"><a href="https://developer.magtek.com/downloads-compliance-and-marketing-materials/downloadable-software/dynafamily-mms-dyna-devices/dynaflex-ii-go"><mark style="color:red;"><strong>Downloadable Software</strong></mark></a></td><td>The essential software resources for developing with and managing the DynaFlex II Go secure card reader.</td></tr><tr><td valign="middle"><a href="/products/dynafamily-mms-dyna-devices/dynaflex-ii-go/compliance.md"><mark style="color:red;"><strong>Compliance</strong></mark></a></td><td>Compliance documentation for the Go, including inspection documents.</td></tr></tbody></table>

### FAQs

<details>

<summary>What methods of payment does DynaFlex II Go accept?</summary>

DynaFlex II Go accepts the following payment methods:&#x20;

* Magstripe
* EMV Contact Chip
* EMV Contactless
* NFC Contactless
* Mobile wallets.

{% hint style="info" %}
NOTE: DynaFlex II Go BCR is equipped with an optional barcode reader (BCR) capable of scanning both 1D and 2D barcodes, expanding its utility beyond traditional payment methods.
{% endhint %}

</details>

<details>

<summary>Does DynaFlex II Go accept RFID and/or NFC technology?</summary>

Yes. DynaFlex II Go supports reading and writing non-payment NFC data for the following:&#x20;

* MIFARE Classic
* MIFARE DESFire
* NTAG.

</details>

<details>

<summary>What operating systems is DynaFlex II Go compatible with?</summary>

DynaFlex II Go currently supports the following operating systems:&#x20;

* USB-C for iOS, Windows, and Android
* BLE for iOS, Windows and&#x20;
* USB iAP2 for iOS

</details>

<details>

<summary>What interface options are currently supported by DynaFlex II Go?​</summary>

* USB-C for Windows and Android.​
* BLE for iOS, Windows, and Android.​
* USB iAP2 for iOS

</details>

<details>

<summary>What barcodes are supported with DynaFlex II Go BCR models?</summary>

The following barcode types are supported by the DynaFlex II GO:&#x20;

* QR Code
* Linear Barcodes
* UPC-A
* UPC-E
* Aztec
* EAN-13
* Code 39 Code 128
* PDF417/ Data Matrix
* Color encoded, Logo-based QR Codes.​

</details>

<details>

<summary>Why is the cardholder name missing from contactless transactions?</summary>

Cardholder names are omitted from Contactless transmission for the following reasons:&#x20;

* **Security against skimming:** Contactless cards use radio waves to transmit data. If the cardholder name were included, someone with a hidden reader could potentially capture it.
* **Privacy compliance:** Financial regulations, including GDPR and GLBA require data minimization. Since a cardholder name is not required to authorize a tap-to-pay transaction, issuers omit it to reduce the risk of exposing personal information to a data breach.
* **EMV standards:** While cardholder name is stored on the chip for "dipped" (inserted) transactions, the contactless protocol is specifically programmed to block that data field. This is why a receipt can show "Valued Customer" or "No Name" when tapped.

</details>

<details>

<summary>How do I tell when my DynaFlex II Go unit has been tampered with or is just suffering from a low battery?</summary>

Your DynaFlex II Go gives off two different LED and audio signals to i ndicate which of these conditions apply:&#x20;

* **If your device has a depleted battery and has NOT been tampered with:**
  * If you attempt to turn on a device with 0% battery charge, the following sequence occurs:
    * The device will power down immediately due to the depleted battery
    * The four LEDs will blink four times in succession (ON/OFF every 0.25 seconds)
    * The device will beep twice with a 500 Hz tone ( ON/OFF every 40 milliseconds).
* **If your device has been tampered with and isn't working:**&#x20;
  * If you attempt to turn on a device that has been tampered with and has 8% battery level or more, the following sequence occurs:
    * The device powers down immediately due to its detected tampered state.
    * After this failed power-up attempt, the following sequence occurs:
      * The four LEDs will blink twice in succession (ON/OFF every 0.5 seconds)
      * The device will beep twice with a 750 Hz tone (200 milliseconds ON / 40 milliseconds OFF)

</details>

### For more help

{% hint style="info" %}
**Need Help?**

For additional support, please contact MagTek Support:

**Technical Support:**

* 📧 **Email:** [support@magtek.com](mailto:support@magtek.com?subject=Support%20Request)
* 📞 **Phone:** 1-562-546-6800 (US)
* 🕐 **Hours:** Monday-Friday, 5:30 AM - 5:00 PM PST

**Online Resources:**

* 🌐 **Support Portal:** developer.magtek.com

**Documentation Feedback:**

Help us improve this documentation! [feedback@magtek.com](mailto:feedback@magtek.com?subject=Feedback)
{% endhint %}


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