> 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/~/revisions/nGirfT12ASLhMZcOe4y9/dynafamily-mms-dyna-devices/dynaflex-ii-scr.md).

# DynaFlex II SCR

The **DynaFlex II SCR** is a compact, countertop secure card reader authenticator
\
(SCRA) that reads contact chip, contactless (NFC), and magnetic-stripe cards and
\
encrypts cardholder data at the point of read (SRED). It connects over USB and
\
uses the shared DynaFamily MMS command set, so everything you build against it
\
is documented in the <mark style="color:red;">**API & Command Reference**</mark> and linked below.

{% hint style="success" %}
**Applies to:** DynaFlex II SCR
{% endhint %}

### 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
* Compact countertop secure card reader authenticator (SCRA)
* PCI PTS POI–approved SCRA for attended acceptance (no PIN entry — see the DynaFlex II PED for PIN debit)

### Build with the DynaFlex II SCR

<table data-header-hidden><thead><tr><th valign="middle"></th><th></th></tr></thead><tbody><tr><td valign="middle"><strong>Section</strong></td><td><strong>Description</strong></td></tr><tr><td valign="middle"><a href="/products/~/revisions/nGirfT12ASLhMZcOe4y9/dynafamily-mms-dyna-devices/dynaflex-ii-scr/programmers-manual.md"><mark style="color:red;"><strong>Programmer's Manual</strong></mark></a></td><td>The MMS command set scoped to<br>the SCR: message format, commands, notifications, configuration, and status codes.</td></tr><tr><td valign="middle"><a href="/products/~/revisions/nGirfT12ASLhMZcOe4y9/dynafamily-mms-dyna-devices/dynaflex-ii-scr/programmers-manual/commands.md"><mark style="color:red;"><strong>Commands</strong></mark></a></td><td>The commands the SCR 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/~/revisions/nGirfT12ASLhMZcOe4y9/dynafamily-mms-dyna-devices/dynaflex-ii-scr/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/~/revisions/nGirfT12ASLhMZcOe4y9/dynafamily-mms-dyna-devices/dynaflex-ii-scr/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></tbody></table>

### Downloadable Software

<table data-header-hidden><thead><tr><th valign="middle"></th><th></th></tr></thead><tbody><tr><td valign="middle"><strong>Section</strong></td><td><strong>Description</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-scr"><mark style="color:red;"><strong>Downloadable Software</strong></mark></a></td><td>The MMS command set scoped to<br>the SCR: message format, commands, notifications, configuration, and status codes.</td></tr></tbody></table>

### 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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