Pyrex Collector Forums

I came across this one on ebay today and I am curious to see what it does. I have never seen one before until I saw the photo in the pattern guide browser here. It doesn't have bids yet but there is still a couple hours on the auction.
http://www.ebay.com/itm/VERY-RARE-PYREX ... 234ff6a72b" onclick="window.open(this.href);return false;

No bids. I think the seller did themselves a disservice by posting such poor photos. I couldn't even tell from their photos that the leaves had any blue at all.