This is a collectors item.
Made in the DDR (former East Germany).
This M42 lens is solidly built and has some good online reviews
https://www.pentaxforums.com/userrev...135mm-f35.html
http://extreme-macro.co.uk/carlzeissjena-135mm/
Disclaimer:
The diaphragm seems to be stuck on wide open (f3.5) and will not step down (not for me anyway!). So it's a fixed f3.5 portrait lens, or an excellent wide field lens, which is what I originally purchased it for.
You can get a range of M42 adapters for your modern DSLR or mirrorless bodies. Comes with end caps and a soft pouch.
$150 posted Aust wide.
PM me if you are keen.
Thanks for looking.
Bo