The Works is selling John Crane's Magic Viewers for £1.99. They were £4.99, apparently, but over on Amazon they're still £4.55.
While I love most John Crane toys anyway, I find products like this, that come with absolutely zero information about them, rather annoying. Perhaps that's why they don't sell enough, so they have to put them on sale? Hmmm... not that that's a bad thing.
Anyway, from the picture of the box, I can tell you that this is a kaleidoscope. You put it to your eye, and look through it while twisting the pole bit and keeping the flower bit still. It's perfect for hot summer afternoons lazily lying under a tree. Yes, you might need to take it abroad to get that.
From all the pictures around the web you'd be forgiven for thinking you get four different ones in the box, but I expect you're buying only one, and it's luck of the draw as to which flowers you'll receive.
They're intended for over 3's, and I think they make lovely little gifts. If you do in fact get all four - even John Crane's website doesn't specify - then it's a really great price, and they'd be fantastic goody bag fillers.