This metal Screw-in Lens Hood, Compatible with Panasonic LUMIX DMC-LX100, DMC-LX100II and Leica D-LUX (Typ 109)
is designed to prevent unwanted stray light from entering the lens by extending and shading the end of the lens. The non-glare matte finish on the inside further prevents or limits lens flare.
No vignetting will show with the hood on.
With the extended lens end, you will also benefit from extra protection from accidental impact.