Neewer 40.5mm Vented Metal Lens Hood Shade for Leica Lens with 40.5mm Filter Thread -Black Protect the lense against unwanted light flares impact, dust and particles etc. Convenience to carry for outdoor photographing It also can be used in the telephoto lenses if you are not using an original Leica lens shade This lens hood not only prevents glare and lens flare, but also provides an extra protection to your lens.