Cat heaven
They must cover the box in some kind of special smell only cats can detect, because our moggie knew it was for her the moment the nice Yodel man delivered it.
She spends nearly all her time on it now, and the built-in box is a perfect hiding place from which to ambush the dog. It's amazingly good value, too.
Also a five-paws review for Bitiba for delivering it next-day, for free, right before Christmas.