my latest find, an Industar 24M 1:3,5/F=10,5cm for Zenit M39 mount. It looks like it has hardly ever been used, with perfectly preserved leather quiver and both caps. I had no idea that such a lens existed, and it seems to have been built only very rarely, as you can see from the serial number.
an interesting website, he has tested a crazy number of lenses. I don't think the pictures with the I-24M are that bad, I like them. And about the Industar 7, nice find. But I also like the FED behind it :-)
By the way, the focusing was very stiff. But if you unscrew the ring with the apertures and then remove the focus ring, you can see a large focus helix. With a bit grease on it, it runs very smoothly again.