Infinity lock is working as designed. Lens focuses correctly as confirmed by my Leica M240 camera. The lens barrel shows signs of normal use with slight brassing.
Lenses from this era are very soft and I would say that this is a very clean example with light marks on the elements (I shone a harsh spotlight through the lens to exaggerate the marks for your inspection). There is no haze, separation, or fungus. Listing includes lens and the following original accessories: front cap, bubble case.
Feel free to message me with any questions. The item "Leitz Leica Summarit 50mm f1.5 11120 Screw Mount, LTM, M39 Lens" is in sale since Friday, December 28, 2018. This item is in the category "Cameras & Photo\Lenses & Filters\Lenses". The seller is "fotonegger" and is located in West Des Moines, Iowa. This item can be shipped worldwide.