This lens hood is a replacement for two Leica S system camera lenses: The 11070 APO-Macro Summarit-S 120mm f/2.5 lens and the 11052 APO-Macro Summarit-S 120mm f/2.5 CS lens. Lens hoods are primarily designed to prevent unwanted stray light from entering the lens, by extending and shading the end of the lens. In addition, since the end of the lens is extended, you also get the added benefit of some extra protection from accidental impact.
 

• Replacement for #11070 Apo-Macro Summarit-S 120mm f/2.5 and #11052 Apo-Macro Summarit-S 120mm f/2.5 CS lens 
• Designed to prevent unwanted stray light from entering the lens, by extending and shading the end of the lens 
• Added benefit of some extra protection from accidental impact