Lens Hood (Bayonet) for 28-70mm f/2.8 D AF-S Lens.Use of specifically engineered Nikon lens hoods is highly recommended.In less-than-ideal lighting conditions, the performance difference can be substantial.Bayonet lens hood provided with select NIKKOR lenses. By reducing the amount of non-essential light falling onto the front lens element, lenses can better achieve their optimum optical performance, producing more saturated images.