The first "all you can eat" music download service that lets users copy tracks to any device with no strings attached has launched in the UK.

Datz will charge £100 for a USB security key that gives people access to its Music Lounge site for a year.

Unlike rivals Napster and Rhapsody, all tracks are in MP3 format, which means they can be burned to CD and played on an iPod or any digital music player.

Users can keep tracks they have downloaded when the subscription ends.

Datz boss Michael Richardson said: "The real target market is young teenagers who are downloading illegally.

"The family won't have to worry about getting nasty letters from the solicitors and the son or daughter gets all the music he or she wants."

"We are not trying to judge ourselves against iTunes. We're taking on [peer to peer networks] BitTorrent and Limewire."

Missing tracks

EMI and Warner Music, two of the "big four" record labels, have signed up to Music Lounge along with a number of independent publishers.

But the site has yet to reach agreement with Sony BMG or Universal Music, meaning artist from Kanye West to U2 and the Ting Tings will not be available at launch.

Boss Michael Richardson hopes to sign more deals over the next six months.

He said: "For the moment our prices won't increase as other labels join in.

"When we look in the New Year, then there may have to be a price rise. I hope not, but there may be."

Datz is the second major "all you can eat" music service to go live this year.

Nokia launched its Comes With Music package in October, charging £129.99 for a mid-range mobile phone with unlimited music downloads for a year.

Rival SonyEricsson is preparing to launch a similar service in January.

But both phone makers are sticking with copyright protected, or DRM, files which force users to play tracks on a limited number of devices.