Original Canon lens hoods are specifically designed for each lens, ensuring no problems with vignetting. Lens hoods block side glare and augment the protection provided by filters to the lens surface and ring. One of the most important accessories for each lens you own. A lens hood provides multiple functions: it shades the lens from stray light, improving your contrast and image quality; in inclement weather, it can assist in keeping moisture or wind-blown debris off the lens; and it protects the front barrel from the inevitable impacts against walls, door frames, and other real-life obstacles. Almost all EF and TS-E lenses have a Canon lens hood engineered specifically for it.