What is this marvelous kitchen tool??

We were given this tool by our son on return from a holiday in Croatia.

Its size you can judge from the fact that the paper behind it is A4

After seeing it and handling it, we were clueless as to its use.

The clue is in the picture where you may see some roast potatoes (a splendid meal with friends last night) and a couple of spiral roast potatoes. The gadget screws into potatoes - or any other hard root vegetable - to make a spiral 'chip' ready for roasting or making into chips.

It was a real talking point at our dinner party, and we believe that 'every home should have one'!