These are original Subaru bolts to hold the compressor bypass valve onto the intercooler. (The compressor bypass valve, also known as a "blow off valve," releases compressed charge air when you back off the throttle.).
It's important not to use too long of a bolt in this location because you can damage the intercooler end tank, and potentially your engine. Use the OEM bolt and be safe.
Set of two bolts.
Fits all 2002-2007 WRX, and 2004+ STI, including 2015+ STI.