Drawing on their 35 years of racing knowledge, the Crawford Closed Loop Air/Oil Separator was engineered and designed to keep all the oil where it belongs, inside the motor. Newly designed for the BRZ/FRS/GT-86 to maintain the OEM PCV valve.
The Air/Oil Separator solves a simple problem from the manufacturer; it transfers the oil back into the engine via the block not the intake. This not only keeps the vehicle within specs of smog but keeps the oil from coating the tops of the pistons.
So if you want to keep your engine running consistently and strong for years to come make sure you install a race and street proven product from leaders in the industry.