K&N Engineering Custom Air Filter Round 4.625in ID / 6in OD / 2.5in HeightK&N Engineering Custom Air Filter Round 4. 625in ID 6in OD 2. 5in Height Universal Fitment Part #: E 3226 Overview The K&N Engineering Custom Air Filter Round 4. 625in ID 6in OD 2. 5in Height is engineered to provide superior filtration performance for off road and dusty environments. Designed for use in a variety of applications, this high quality air filter helps protect your engine from dirt, debris, and other contaminants while maintaining optimal