What is it? A sock within a sock.

Don't be gnomic. The inner layer stays with the foot, the outer layer moves with the shoe.

So? Friction on the skin is eliminated and wear is reduced.

Meaning? You don't get blisters and they last a 1,000 miles.

Can this be true? That's what the guarantee says from 1,000 Mile Sportswear.

Do they quibble? No, in fact they give three or four refunds a week. But that figure hasn't risen while sales have trebled in the past four years.

What else do the socks do? Combat sweaty feet. The moisture moves naturally to the drier outside layer - especially if the inner layer is made from Tactel.

What's that? A synthetic nylon fibre that draws moisture away from the skin. You can also get them in wool, cotton and combinations thereof.

Who uses them? The first use was medical, for people with poor circulation. Then runners began using them. Now increasingly walkers and golfers are investing in a pair.

What do they cost? Between £8.99 and £12.99. There are 50 different styles and lots of colours.

Where do I get them? Specialist outdoor shops: for local stockists call 01923 242233.

Not to be confused with: The 1,000 Guineas, hundreds and thousands, thousand-island dressing.