It works best with large aperture parameters. It is recommended that you keep the aperture above F/8.0.

hello， the filter is made of glass

The way u tell is to look at the end of you lens. There will be a 0 with a slash / through it and a number behind it. Match that number to the 58 of this neutral density filter.

Dear Customer, there is no circular polarizer in it.Please order circular polarizer here https://www.kentfaith.com/cpl-filters.

It depends on what your shooting with a polarizer filter. They mainly are used to block reflections and glare that sort of thing. So, maybe it can work I've never done that myself though. Hope this helps!