PCI Express M.2 specification-Revision 0.7, Version 1.0,November 27, 2012,
The M.2M.2 form factor is used for Mobile Add-In cards. The M.2 is a natural transition from the Mini Card and Half-Mini Card to a smaller form factor in both size and volume. The M.2 is a family of form factors that will enable expansion, contraction, and higher integration of functions onto a single form factor module solution.
The key target for M.2 is to be significantly smaller in the XYZ and overall volume of the Half-Mini Card used today in mobile platforms in preparation for the very thin computing platforms (for example; Notebook, Tablet/Slate platforms) that require a much smaller solution.
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