Hi to all of you!

For some time I'm reading the pages of this forum and I found a lot of great information on old hardware and stuff like that, but now I'm stuck and I need your help identifying this socket adapter. I think it is a socket adapter(voltage regulator)... maybe socket 7, but I can't find any info on the net.
Here are some pictures of it:

If someone knows what it is and has some info on it, a manual, jumper settings, etc. I'd appreciate any help.

Thanks a lot!