Can you tell what it is? Of course you can. It's a vacu vin pineapple slicer -
(You now know how to say 'pineapple slicer' in ten languages.) You top and tail your pineapple, then simply drill down through it. It takes out the core, and you're left with this -
Oh, and some pineapple rings.
If you'd been given one of these for Christmas, would you have believed it actually worked? Nope, me neither. But it does, effortlessly! It's the best thing ever invented. I do like it when they get something right.