I also notice there are couple of sellers on fleabay offering newest B+W polarizer at amazingly low price. Could it be counterfeit products?
Lots of plastic filters are being sold from Chinese sources; no doubt they find their way onto eBay as well. It wouldn't surprise me if some cocky sellers offer "B+\/\/", "8+W", "B&W" etc. filters, - or even just plastic fakes with the actual B+W logo/brand name printed on.
"If it looks too good to be true, it probably is".