Over 50 million yellow Livestrong wristbands have now been sold, raising millions of pounds for charity.
The rubber bands, launched by top cyclist Lance Armstrong a year ago, are being sold to raise money to help people and their families fight cancer.
Six times Tour De France winner Lance was told he had cancer in 1996 and beat the disease.
Since the Livestrong bands came out wristbands have become a craze with loads of other causes releasing bands.
At first the Lance Armstrong foundation was worried it would find it hard to sell the initial batch of six million wristbands produced.
But sales caught on fast and soon millions of people were snapping up the distinctive yellow bands.
Fake band warning
The bands, made by Nike, have been spotted on the wrists of loads of celebs including actress Angelina Jolie and Bono from U2.
In March this year people were warned to look out for fake Livestrong bands, and charities urged people to only buy bands from official shops and websites.