Nikon HR-1 Collapsible Rubber Lens Hood Suitable for various 50mm Nikon lenses.It will fit other lenses too, such as the 70-210 AF zoom.  Check via a search engine for applications; I used this one on a 50mm f1.8 Ai.

In good condition with light marks here and there, but does what it says on the tin.

Thanks for looking.