Filter Lens Nikon

Filter Lens Nikon
What I need to filter for a Nikon D40 with 18-55mm lens?

The answers as soon as possible, please! ONE SIZE!

The filter is only recommended to be a protective UV filter or 1a, and, possibly, a Polaroid filter. Filters for color correction are not necessary as they can do that with the D40 or the software on your computer. Sizewise, 18-55mm has a 52mm filter diameter.

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