Football fans are buying Oxford Loyal wristbands for up to 20 times the original price - even though they are available for £1 from the club again.

The yellow bands have proved so popular that a buyer on the internet auction site eBay has paid more than £21 to get one from a seller in Witney - while another seller in Harrow, Middlesex, had two bands up for grabs with a Buy It Now price of £25 but failed to clinch a sale.

Some of the listings on the site describe the wristbands as 'sold out', but in fact the shop at Oxford United's Kassam Stadium has just taken a delivery of 2,000 bands after it sold the 6,000th - thought to be the last - in September.

The wristbands were produced by the club and the Oxford Mail so fans - like Stuart Shaw, from Didcot, could show their backing for the team with profits going to charity.

Oxford United spokesman Chris Williams said the club would prefer fans to pay the smaller fee of £1 at official outlets and give to charity at the same time.

He said: "Obviously we cannot control what fans do once they have brought the wristbands.

"Any fans thinking of buying from eBay might want to consider getting more of them for the same money from the club shop because half the money goes to the Oxford Children's Hospital Campaign and the other half goes to Us Youth.

"I saw them on eBay and it was being marketed as no longer available which is slightly false marketing because we have just had 2,000 delivered. I am always amazed at what people will sell on eBay.

"We would prefer the money went to charity and helped the club and a great cause rather than someone who wants to make a quick profit."

But charity is benefitting from one eBay seller.

Adam, a 17-year-old from Bicester, got £13 for the wristband he put on eBay - but all that money will be going to the Oxford Children's Hospital appeal.

The teenager put the band on the site with a 50p price tag, which within two days had climbed to £2. A bidding war then developed between 'ianwiddows86' and gazzerk', pushing the price up to £7.

But both bidders were outbid in the last days by 'danieleymer' who was willing to pay £12.50. However he himself was outdone by 'mr-nigel' who had put in a reserve bid of £13 two days earlier.

Adam said: "I was surprised because there was a couple of other bands on there. I don't know whether that money goes to the hospital or if they keep it.

"People who bid for it don't make a cheque out for me, they make a cheque out to the hospital. I am really pleased, because they only cost £1 so the hospital are making £12 more."

Adam, an Oxford United season ticketholder, has his own wristband to keep.

He bought a few of them when they first released because he thought they would be a collector's item.

"I thought they were a great idea," he said.

He has another seven to sell on eBay - with the profits promised for the Children's Hospital.