The Mishimoto Baffled Oil Catch Can Kit is designed and engineered to work on your WRX to eliminate harmful blow by vapors from re-entering your engine. The EJ25 in the WRX is known for producing blow by gases during normal to severe driving, especially when more boost and horsepower is added to the engine. This oil blowby can work its way into your intake system, reducing the octane rating of your fuel and potentially causing damaging detonation, which has a profoundly negative effect on the already sensitive EJ25 engine. The kit uses our small baffled catch cans with a bronze filter, and internal baffled to better separate the oil from the crankcase vapors. The turbo inlet side of the kit utilizes our three-port baffled catch can to catch as much oil vapors as possible. It also includes two direct fit mounting brackets that not only is extremely easy to install but also fits right hand drive as well! The kit comes with six direct fit hoses that fit as if they were stock. The hoses are designed to fit right onto the PCV valve ports and into the turbo inlet ports. Plastic, barb fittings connect the hoses to the can. Like all of our products, this baffled catch can kit comes with Mishimoto's lifetime warranty! Our catch cans are different from most air-oil-separator (AOS) systems on a few levels. First, our catch cans are not heated. This means that all of the blow-by is able to condense in the can, including low-octane oil vapors and contaminated fuel vapors. Most AOS systems also drain the blow-by back into the oil pan, while our catch cans trap the blow-by and keep it out of the engine permanently. If you've seen what We've seen in the bottom of our catch cans, you won't want that draining back into your oil either.