I use this more often than my U.V.
When I don't need it any more the U.V. goes back on, but either one is cheaper to replace than a lens. Since I read an article about using a Polarizer for Portraits I've been useing it with great results, someone wrote into the same magazine asking about useing a Polarizer for cars which is my main use for my Polarizers. Don't wait until you take a picture through glass or of some fish and you can only see reflecions of other things to buy a Polarizing Filter.
P.S. this is as thin as my other Slim Polarizer but I can screw a filter onto the front of it much deeper.