The distinctive blue-and-white striped shirts that are standard issue for the inmates of Britain's jails have become a symbol of rebellion among the trendy young.
Made at HM Prison Haverigg in Cumbria, they have a cachet emphasised by rarity value, and the fact that every one is guaranteed smuggled out by a con.
Under jail regulations, prisoners hand back their uniforms in exchange for their own clothes when they finish their sentence. But with 53,000 people now locked up in Britain's jails, and each prisoner issued with at least two shirts, the opportunities for smuggling have grown as demand has soared.
Michael Sullivan, who makes his living dealing in St Paul's, Bristol, has no doubt of the value of the shirts. "People pay for the label. The prison crown is as valuable as Calvin Klein. People who wear it want others to think they have been inside."
One ex-convict brought his shirt out of jail in the base of a board game after serving three years for robbery. It bears the initials of Earlstoke Prison, Devizes, Wiltshire, and in London it could fetch up to pounds 50.
Another prisoner established a sophisticated trading operation in shirts when he was let out of prison each day to work. Once beyond the walls he hid packs of 10 shirts in a churchyard, later informing friends where to pick them up.
On the streets, rarity is part of the attraction. "If the market was flooded nobody would take them seriously. You'd have kids wearing them who no way had done time," said Mr Sullivan.
The Prison Service is so concerned that it has helped with the police in operations against market traders. "We are aware of a problem. We are very keen to get any of our property back," said a spokesman. He added that he could not see the attraction. "I certainly wouldn't wear one."
But was this not a chance for the Prison Service to show some enterprise and raise some extra cash? "I don't think so. Prison wear is distinctive so that prison officers and police can identify it," said the spokesman.Reuse content