Attached Link: http://www.hoyafilter.com/index.html

@dBgrafix....sorry, you're right link does work. @mayday...I have attached the link to the Hoya site...maybe that will help some more. There are some other differences...yes, more layers, but also thickness and whether it has double threads. I know more layers= more $....I am not sure if it is worth the money though. Maybe someone else has some experience with the different types....

In youth, we learn....with age, we understand.