Holds 2 cards for super large capacity. Card types can be mixed. Cards of different capacity and different type can be used concurrently (i.e. microSD + microSDHC). Specification / Features: Model: CR-5400 OS: Windows Vista XP,2000.Me,98SE,Mac OS 9.2,Mac OS, X,Linux Support: MicroSD 256MB â?? 2GB / MicroSDHC 4GB -16GB Speed: Super high read/write speed of 10 MB/s and up Size: 32mm x 20mm x 1.6mm(L x W x D) Package Includes: 1 x CR-5400 adapter Please take note of this step- by step instruction: 1. Format both micro sds in Windows. 2. Put them (the larger in the slot #1) inside the pro duo adapter. 3. Put the adapter inside the PSP, turn it on, and format the SD from the PSPâ??s XMB (Format Memory Stick) and choose yes. Both micro sds will become one , so if you add data then do it through the adapter(card reader) or the PSP in this case, do NOT ever add data per micro sd individually, as the data will get corrupted. Data Transfer can only be done with micro SDHC cards inserted in CR-5400. Direct PC to micro SDHC card data transfer and then inserting in CR-5400 wonâ??t work. Should you experience formatting problems (i.e. only half of the original capacity available), please format concerned micro SDHC card(s) in slot#1 of CR-5400 (slot#2 must be empty). Do this for every affected card. Now you can re-use your micro SDHC card(s) in other devices. If only 1 microSD(HC) cards is used, it must be inserted into slot#1 in order to work. When using new microSD(HC) cads, you need to format with a product before you can store data. In order to copy or delete data directly, insert CR-5400 in your card reader. Donâ??t take out the microSD(HC) cards and perform write operations on the single card. Your data will be corrupt.