The integration of a memory function with a connectivity function will improve the versatility of the devices.
Until now users who were connected to the Internet via Wi-Fi, had to rely on the portable device's built-in memory as the Wi-Fi card occupied the slot where a memory card would usually fit.
If the built-in memory was nearly full, this prevented users from downloading some files. The new combination memory/connectivity cards will let users access the memory while connected to the Internet and so provide greater space for files, said SanDisk.
The company's SanDisk Connect range initially includes two combo cards: a CF card that combines Wi-Fi and 128Mbytes of memory, an SD card that combines Wi-Fi and 256Mbytes of memory.
The smaller card will be available in the US from March for $130 (£81) and the larger will be available in the middle of 2003 for $150 (£93).
SanDisk is also releasing a pair of Wi-Fi cards with no built-in memory. A CF Wi-Fi card is available now and an SD Wi-Fi card will follow in March.
Both the Wi-Fi and combo CF cards include a PC Card adapter to allow the devices to be used in notebook personal computers. SanDisk also said it is planning a CF combo-card with 256Mbytes of memory in the middle of the year although it did not release pricing details.