A lens hood is an essential part of your system. By reducing stray light and minimizing flare, your pictures show improved contrast and better color saturation. Hoods also provide important stock protection, should your lens be dropped or bumped. Geniune Nikon hoods are made of materials that prevent permanent bonding to the lens, which may sometimes occur with other manufacturers' hoods. Available in four types:Screw-in hoods screw onto the front of the lens. Metal types are available for extra strengh. Rubber types fold back over the lens when not in use.The Nikon HB-25 Lens Hood is compatible with the 24-85mm f/2.8-4.0 D-AF lens.