The xtra xtra Pro, designed for the Palm IIIx, is the latest in this line. It not only doubles the available RAM to 8Mb, but also provides an additional 2Mb of non-volatile Flash memory. Pro is TRG's FlashPro software, which allows use of unused Flash memory for applications.
Installation is relatively simple.
Online instructions are available, and the board previously available only with Japanese packaging, recently became available with English packaging as well. The back cover of the Palm IIIx must be removed, and the board is then snapped into the available expansion slot. Once the xtra xtra Pro is installed, onboard RAM is disabled in favor of the RAM on the xtra xtra Pro, so a HotSync must be performed to restore all user data. Use of BackupBuddy NG or a similar product is recommended to prevent loss of data. Current users of FlashPro will find it necessary to reinstall the software, or rerun FlashPro Setup, so that the software will recognize the newly available Flash.