Vintage telephoto prime lens for L39 mount cameras.
The Canon L39 135mm f/3.5 is a telephoto lens for the Leica Thread Mount (LTM/L39) bayonet system, produced by Canon for their rangefinder camera bodies (Canon 7, Canon P, Canon L-series). L39 refers to the 39mm screw thread mount compatible with Leica and Leica-mount cameras of the era.
135mm focal length, f/3.5 maximum aperture, Leica Thread Mount (L39/LTM) screw mount, designed for Canon and Leica-compatible rangefinder cameras.
Canon's rangefinder-era L39 lenses are high-quality Japanese-made optics from the 1950s–1960s, produced when Canon's rangefinder cameras rivalled Leica in quality. The L39 mount makes these lenses compatible with Leica M cameras via an L39-to-M adapter, extending their usability to the large Leica M user base. The 135mm provides telephoto reach on a rangefinder platform.
Inspect for fungus, haze, and coating condition. Confirm L39 thread engagement is clean and un-cross-threaded. Check aperture blades for oil. Note that the 135mm focal length on Leica rangefinders requires the 135mm bright-line frame in the viewfinder (available on Leica M3, M2, M6, etc.).