# SD card types-help with phone?

**URL:** <https://boards.straightdope.com/t/sd-card-types-help-with-phone/758493>\
**Category:** Factual Questions\
**Created:** [June 27, 2016, 2:06am UTC](https://boards.straightdope.com/t/sd-card-types-help-with-phone/758493 "2016-06-27T02:06:04Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Cardinal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cardinal/32/4000_2.png) [@Cardinal](https://boards.straightdope.com/u/Cardinal)\
**Post date:** [June 27, 2016, 2:06am UTC](https://boards.straightdope.com/t/sd-card-types-help-with-phone/758493/1 "2016-06-27T02:06:04Z")

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I was researching the Motorola Moto X Pure, Third Edition, and I see a couple notes made about the expandable memory. [Swappa.com](http://Swappa.com) says “128.0 GB max + MicroSD 2.0 compatible”.

The user guide says to use a class 10 memory card. Can someone tell me what the intersection of these two ideas is? What do I search for on eBay?

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**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\
**Post date:** [June 27, 2016, 2:31am UTC](https://boards.straightdope.com/t/sd-card-types-help-with-phone/758493/2 "2016-06-27T02:31:19Z")

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Class 10 is the transfer speed: [Speed Class | SD Association](https://www.sdcard.org/developers/overview/speed_class/)

MicroSD is the size.  
2.0 presumably is meant to be the SDA spec, which is up to 4.0 now (2.0 came out in 2006):

> **[SD card](https://en.wikipedia.org/wiki/Secure_Digital)**
>
> Secure Digital, officially abbreviated as SD, is a proprietary non-volatile flash memory card format developed by the SD Association (SDA) for use in portable devices.
> The standard was introduced in August 1999 by joint efforts between SanDisk, Panasonic (Matsushita) and Toshiba as an improvement over MultiMediaCards (MMCs), and has become the industry standard. The three companies formed SD-3C, LLC, a company that licenses and enforces intellectual property rights associated with SD memory card...