Heliopan 39mm Screw-in Rubber Lens Hood

The Heliopan 39mm Screw-in Rubber Lens Hood is designed to prevent unwanted stray light from entering a lens by extending and shading its front end. This prevents lens flare and improves image contrast. In addition, since the end of a lens is extended when using a hood, you also get the benefit of extra protection from accidental impact to that lens's front element.