Improve visibility and reduce flare with the black MH-RA 55mm Lens Hood for the Pentax DA 20-40mm f/2.8-4 ED Limited DC WR lens. The slim accessory is designed to block stray light from entering the lens, without appearing in your frame and causing vignetting. Additionally, since it protrudes beyond the front element, the hood protects the glass against light impact. It is included with the lens and offered here as a spare or replacement part.