This is a classic, Made in Germany series, Leica 13.5cm (135mm) f4.5 Hektor - Black barrel lens. This lens (#600320) shows to be from 1945 (War Time) with a very unusual triangle etched marking on both the barrel (near the tripod socket) and the lens head (near the serial number.
This is a great classic lens for Rangefinder cameras with M39 (Leica LTM screw mount) and others with a proper adapter too - Film and digital cameras alike.. This lens offers a really nice design allowing it to mount to a tripod directly making it easy to secure a nice center of gravity balance. it offers a removable front lens head allowing it to be used on bellows and additional macro items too (I have even seen them used on large format view cameras before) with high detail and great sharpness.....
This lens comes exactly as shown; showing paint wear from use with very nice glass and works great too.. The focusing moves nicely , The glass is nice and has No scratches, No fungus, light dust, good coatings. A great working lens, great quality optic... This lens has been fully camera tested with wonderful results.