I've used K&F filters in the past and have not been disappointed. These filters are no exception. They fit perfectly on my Air 3S. Gimbal guard still fits perfectly when these are installed. I'm not seeing any strange vignettes nor flaring issues. The colors pop and the CPL effect works as expected. The gimbal is not giving me any strange warnings, nor mistaking it as a wide-angle lens adapter.

Previously, I tried the Sunnylife CPL filters since they were the first to be available for the Air 3S. I returned them because my 3x lens had trouble focusing. I've tested these K&F filters on the 1x and 3x lens, no focusing issues at all.

These aren't like the stock DJI Filters that come with the fly more combo. Those filters (thought they don't offer the CPL effect) compensate for the different apertures of the 1x and 3x lenses, allowing you to have the same shutter speed and ISO settings if desired. (Google and YouTube will be your friends here if you need a more detailed explanation.). These K&F ND/PL filters are for anyone who wants to add more pop, color and contrast to the already excellent image quality coming out of the Air 3S. Also, if you work in architecture or near large bodies of water, you probably already know how valuable removing reflections are to you in those industries.