Satisfaction guaranteed. My goal here is what I view as a win-win: I'm offering these at a price that doesn't even really pay for my time, but I really would like these useful items to become useful again, as a kind of pushback against the cycle of excessive consumerism. You can get better polarizers for sure, but these are more than adequate for almost all purposes — I use one myself to make all my listing photos, for example. If you're not delighted with what you get, just let me know.
Most of the filters in this listing are vintage 1970s-1990s but occasionally there will be a modern one. There are a few prestige brand filters like Nikon, and major third-party brands like Tiffen and Hoya. Most will have brand names like Vivitar, Quantaray, Prinz, UGC, Rokinon, Cambron, Toyo, Promaster, Jessop, Kalimar, Toshiba, CPC, Access, Tokina, Rolev, Albinar, Kenko, Asanuma, Calumet, Spiratone, Samigon, Sunpak, Soligor, etc. Most are made in Japan; some in China, France, Korea, Philippines, USA, USSR or other places.