Review on K&N Engine Air Filter: High Performance, Premium, Washable Replacement Filter for 2010-2019 Mazda L4 2.0/2.3/2.5L (CX-5, 3, 6, Atenza, Biante, Premacy, Axela) - Model 33-2480 by Jeff Bridgewater

Replaced the stock air filter in my 2015 Mazda 6 Sport with this one. I saw an increase of about 2mpg on the first full tank of gas after installation, as well as noticeably better acceleration (the engine feels like it doesn't have to try to pull in air as hard as it used to). Maybe this part is just in my head but the difference in MPG is definitely real. This filter is washable. It has a fine mesh covering the cloth portion of the filter so you can wash and re-grease it every 50,000 miles or so. Will update rating if performance changes, but so far so good!