Screw Lens Hood

Screw Lens Hood
What kind of hood should I buy for a Nikon 50mm 1.8 lens?

I'm just asking becuz I bought an umbrella once used by a cameraman possess, and that was the right size and secure cable, but could be seen in the pictures. All my photos had a black ring around them, somehow was becuz wrong size and I do not want to buy a bad one again.

The Nikkor 50mm f/1.8 lens takes the Nikon HR-2 http://www.nikonusa.com/Find-Your-Nikon/Product/Camera-Lenses/2137/AF-NIKKOR-50mm-f/1.8D.html As Fhotoace said, it is rubber, and screws as a filter that is not a fancy parasol.