What filter size does the leica elmarit m 28mm f 2 8 asph take?

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From Leica Elmarit-M 28mm f/2.8 ASPH: Leica Elmarit-M 28mm f/2.8 ASPH: A prime lens by Leica for Full frame cameras, 28mm f/2.8. One of the smallest M lenses. Specs - Maker: Leica - Focal length: 28mm (prime) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Leica M - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Leica M): as marked, 28mm. Cameras it fits - Leica M9: Full frame - ...

From Leica Elmarit-M 24mm f/2.8 ASPH: Leica Elmarit-M 24mm f/2.8 ASPH: A prime lens by Leica for Full frame cameras, 24mm f/2.8.

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