"SanDisk has begun to sample 12-gigabyte (GB) microSDHC flash memory cards to major phone manufacturers for testing and evaluation.SDHC is the designation for any SD or SD-based card that is larger than 2GB and adheres to the new SD 2.00 specification required for cards and hosts to support 4GB to 32GB capacities. The specification was developed by the SD Association, an industry standards board, which has also created three classes to define minimum sustained data transfer speed. These cards adhere to the SD Speed Class 4 Rating." via slashphone.com