A record company is launching pocket-sized CDs in the UK in an effort to revive the music singles sales market.
50 Cent's music could feature on the mini CD
Universal is to trial the CD, three inches (7.6 centimetres) in diameter, which can carry music as well as mobile phone ringtones to download to PCs.
Artists available will include 50 Cent and The Rasmus.
Universal said it believed there was still a market for singles, while adding ringtones would make the pocket CD an "an attractive purchase".
The mini CDs were launched in Germany but BMG withdrew them after retailers complained that the unusual-shaped format made it difficult to stock.
Universal is planning to phase out the sale of copy-protected CDs in Germany, where music piracy has hit the industry, following concerns that not all would play in some stereo systems.
It said it may re-introduce copy-protected CDs at a later date if and when the technology improved.
The pocket CD is being seen as a marketing tool to persuade young consumers to return to buying CDs rather than downloading music from the internet, whether legally or illegally.
"We believe there is still demand for a physical single format, and hope that folding in a ringtone will make pocket CDs an attractive purchase," collectible - purchase," a Universal Music UK spokesman said.
"That said, it is a very early days, and this is purely a test to see how the market responds," he added.