This semicircular seal fits into the back of the head to seal against the valve cover on most EJ motors. Over time they can get brittle and break. OEM Subaru part. Fits all 2002-2014 WRX, 2004-2007 STI, Legacy and Outback 2005-2009, Forester XT 2003-2013. Does NOT fit 2008-2014 STI.
Sold individually. There are four total on the motor.