Copper

[yrneh1938]

ANYONE TRIED THE ORIGINAL COOPER HEALER
THAT GOES INTO A SHOE
TO HELP BACK PAIN

[Buenchico]

Ruddy 'eck!

They're flamin' expensive!

There are 132 reviews on Amazon here:
http://tinyurl.com/ydb824x9
Exactly half of those (66) give the product a 5 star rating but it's important to note that a significant number of the other reviews rate it as worthless.

A separate Amazon listing has 211 reviews. Once again, most of the reviews are positive but there are still plenty of people who see the product as a total waste of money:
http://tinyurl.com/y6wjogom

Not a bad profit though for an inventor who started with just a few 2p coins!
http://www.express.co.uk/news/uk/340518/I-cured-my-arthritis-by-putting-two-pence-coins-inside-my-shoes

[Old_Geezer]

Then use the coins.

[EDDIE51]

It does nothing that putting a 2p coin in your shoe would not do equally well, if it does anything at all that is!
I am reminded of the magnets that women were supposed to use to cure PMT. The same result could be obtained by putting two fridge magnets down your knickers, but at a cost of a few pence rather than £28 each !

[douglas9401]

Magnets down your knickers?

Can't see the attraction.

[Denton]

Best answer for Douglas9401.!!