Using this K&N Black Typhoon Short Ram Air Intake System is a great way to boost your Subaru WRX's performance. Installation is do - it - yourself friendly. Just grab some hand tools and take your time to install it. But remember, you'll need to tune your vehicle with a compatible off - the - shelf tuning device after installation. When it comes to maintenance, the oversized filter in the system can go up to 100,000 miles before its first servicing. However, keep an eye on it and clean or replace it as needed. And here's a big heads - up: This product can't be sold or used in California on emission - controlled motor vehicles. Make sure to check your local regulations before using it to avoid any legal issues.