This OEM-quality belt fits 2002-2007 WRX and STI, and most other similar vintage Subaru models with an AC belt tensioner. It’s made by Mitsuboshi, the same company that makes the factory Subaru belt. It probably IS the exact same belt; but since it doesn’t go through the Subaru dealer network, it costs a lot less.
Does NOT fit 2008+ Subaru models that have no AC belt tensioner.