Subaru Post MAF Hose712010 The 4 ply silicone construction has the right compliance to bridge the chassis mounted airbox to the violent motion of a boxer engine being driven in anger, while the steel reinforcement prevents collapse when the turbo is drawing maximum vacuum at wide open throttle. Say hello to the new COBB Post MAF Hose for the '02 '07 Subaru WRX! The COBB Post MAF Hose balances form AND function with its smart appearance and turbulence taming