Sales of removable memory cards for mobile handsets will be worth over $7bn in 2007, market watchers predict.

The figure eclipses the $5bn total revenues expected from headset shipments including Bluetooth and wired headsets, according to a recent study from ABI Research.

The analyst firm predicts that memory cards will continue to be the highest revenue-generating mobile phone accessory category over the next five years.

ABI Research industry analyst Shailendra Pandey said: "With few exceptions, memory cards for handsets are bought by users separately from the handset purchase, whereas an increasing number of headsets are now being supplied with the handsets.

"Earlier handset vendors only provided wired headsets, but now even Bluetooth headsets are being presented with the handsets.

"Therefore, greater aftermarket sales of memory cards versus increasing inbox sales for headsets are resulting in stronger growth and higher revenue from memory cards when compared with headsets."

The recent announcement by Nokia, Samsung, Sony Ericsson, Spansion, STMicroelectronics, Micron Technology, and Texas Instruments of support for the creation of the UFS (Universal Flash Storage) specification for use in mobile phones, digital cameras, and other CE devices is likely to fuel the rapid growth of the memory card market.

The UFS standard, expected to be finalised in 2009, will provide a unified memory standard for embedded memory and removable memory cards, eliminating the need to have adaptors for different memory card formats.

"A greater number of handset accessories (including memory cards) will be supplied as handset vendors recognise that to boost sales of high-end, feature-rich mobile phones and smartphones, they need to offer accessories that allow users to benefit fully from the multimedia features in those handsets," added Pandey.

ABI Research expects the market for mobile phone accessories to grow steadily in the next five years, generating over $80bn in revenue in 2012.