How to fit Zykkor Super Wider Semi Fisheye lens on Nikon D3100?

My uncle gave me a fisheye lens, It's a Zykkor fisheye lens and it says it's 55mm. I tried putting it on the lens on my Nikon D3100… Then lens says it's 18-55mm. So shouldn't the fisheye lens fit perfectly on my camera's lens? I tried putting it on my camera and it just won't fit! What size fisheye lens do I need to get for my camera? Or am I just putting the lens on wrong or something?

No, it won't fit. Your 18-55 has a 52mm filter thread.

Your 18-55mm lens has a 52mm filter thread.
If you really want to use it, you can get a 52mm to 55mm adapter ring for it for a couple bucks off amazon.

Get a stepdown (or up?) ring that will connect the 55mm end of the semi-fisheye adapter to the 52mm filter thread of your lens.

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