The Mishimoto Ford Fiesta ST Baffled Oil Catch Can is designed and engineered to reduce carbon buildup, a common issue with direct fuel injection engines. Thousands of test miles were logged on our Fiesta ST to determine what can setup would work the best. Mishimoto engineers found that most vehicles, placing the catch can in the vacuum assisted PCV system of the vehicle will yield the most amount of oil accumulation during normal and aggressive driving. Where a catch can placed on the crankcase vent system on the left side of the engine will yield nearly no accumulation on stock or lightly modified vehicles. Having only one catch can, tied into the PCV system will, by far, work the best for the vast majority of Fiesta ST's on the road. The Mishimoto Ford Fiesta ST catch can kit uses the Mishimoto 2-Port Compact Baffled Oil Catch Can with a bronze filter, and internal baffled to better separate the oil from the crankcase vapors. The kit comes with two direct-fit silicone hoses with pre-assembled quick-disconnect fittings for a simple installation. It also includes one direct fit mounting bracket that not only is extremely easy to install but also mounts the can in a serviceable location! Two CNC-machined aluminum, " barb fittings connect the hoses to the can. Like all of our products, this baffled catch can kit comes with the Mishimoto 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.