This is a brand new bare Subaru EJ257 short block case. It does not have a crank, pistons, rods, or bearings, and is just a plain case.
If you are going to be building a block with forged pistons, or more, this is a perfect way to start because you can pick all the parts you want to put into the block, including your crank and bearings, and this usually comes out a good deal cheaper than starting with a complete block.
The original part number for this case is 11008AA950, which has superceded to 11008AA930.
The case is the same on all USDM STI's from 2004 - 2010, and is also the same block found in the EJ255 engine found in the 06+ WRX and 05+ Legacy GT.