It works! Just as well as any other bracelet! Plus a placebo effect if the sucker who paid for it believes that it is Good Stuff!
Isn't that wonderful? All that healing when it enriches con artists into the bargain?
By the way, are you looking for a second-hand car? I think I can find you a real snip, one that you can hang from your bracelet, whether magnetic or copper or bionic or woven grass! Personalised yet!!! Special price, just for you. I might even accept your house as down payment.
As for those magnetic healing devices, log into the most loathed, most meritorious site on the Web: http://www.quackwatch.com/ Search for magnetic items. It will tell you far more than the quacks would want you to worry your curly little head with. No wonder they hate it. There should be a law against exploding people's comforting delusions, let alone interfering with honest quacks' business.
If there is any merit to half the "alternate remedies" on the market, including such garbage as homeopathy and bangles, then the supporters of Quackwatch will surely sprout fungi from all their pores and go straight burning in hell. You might find it entertaining to begin by reading their "Cheers and Jeers" column.
I don't promise that reading them will cure you of anything, but if they do happen to cure you of believing in quackery, you will owe them and owe them!