Sony Xperia SGPT12 Help Manual page 40

Compatibility of SD Memory Cards
SD memory cards (up to 2 GB), SDHC memory cards (up to 32 GB), and SDHC UHS-I memory cards (up to 32
GB) available as of August 2012 have been tested and found compatible with your tablet device.
However, this does not guarantee that all SD memory cards, SDHC memory cards, or SDHC UHS-I memory
cards will be compatible with your tablet device.