The IAG AOS conversion kit is designed to switch the upper breather portion of the V2 Competition Series AOS to the V2 Street Series AOS on the 2006-14 Subaru WRX and 2004-21 STI. The kit includes the new billet aluminum Street Series double breather, 1/2" hose, 3/8" hose with integrated PCV valve and breather fitting, 90-degree fittings, straight unions and associated hardware.