Excerpt: I purchased the Nikon HB-4 to use on a Nikon 20mm f2.8 lens. I could not be happier with this choice. It fits the lens extremely well while staying very compact for carrying. I am very happy with it.
Pros: Durable, Easily Interchangeable, Fast / accurate auto-focus, Lightweight, Rugged, Strong Construction
Excerpt: After 10 years of owning the 20mm 2.8 Nikon lens I finally bought the hood. It good but sometimes it doesn't stay in place. It's just a twist lock and doesn't have any real locking system so it will sometimes come off if it's bumped. It's a little smaller than I thought it would be. Helps a little to keep the flair out of the lens from side angles. 50/50. Good about half the time. I'd still buy it as it doesn't take any room in the bag.
Excerpt: I bought the Nikon version of this hood (vs independent brand) expecting the best fit, but was disappointed to find that I could not get this hood in place with a reasonable amount of force. While the 20mm AFD is quite a well-made lens, I was afraid to twist the hood any harder onto the bayonet mount fearing that the lens barrel might come out of alignment.
Excerpt: Plastic and looked not very strong. It is the only hood option for an ultra wide lens like AF20/2.8D. Any other choice? A bit expensive for the material use but just right for the design for no dark corners. The ultra wide lens can have dark corners if used with something else as hood other than the HB-4.