About all you can tell from the pic is if it is the correct kind of diff, (specifically a side-loader) which it is.
There will be a small, flat, stamped section on the other side of the diff (the non-pictured side) on the bottom edge. It will tell you the ratio and if it is a LSD. If it is a LSD, there will be an "S" stamped on this tab. This, of course, assumes that nobody opened it up in the past and changed the guts, but that is a pretty infrequent event due to the costs and specialized tools required.