This Leica Lens Hood is designed for use with the Leica Vario-Elmarit-SL 24-90mm f/2.8-4 ASPH. Lens. Lens hoods are primarily designed to block unwanted stray light from appearing within an image by extending and shading the end of a lens. Since the end of the lens is extended while using the hood, some extra protection from accidental impact is also provided.