Detroit locker

Eaton has nothing to do with that piece. That is a Detroit Automotive Products company (DAPCO) locker, known as a Detroit locker..
Their logo follows the 81310 number.
If it's not broken inside, it's the strongest lsd you can get. Also, the noisier (around corners).
Edit: apparently Eaton bought DAPCO, and may not make that part any more. Can't find it at summit .