BMW 523i Replacement Air Filters

Buy now from K&N's Online Store and get a 100% money back guarantee on any BMW 523i air filter!

• Designed to Increase Horsepower and Acceleration
• High Air Flow with Excellent Filtration
• Top Performance Accessory for BMW 523i Models
• K&N Million Mile Limited Warranty®

Order your K&N replacement air filter Factory Direct today! Help your BMW 523i run better. Fast and FREE SHIPPING with any BMW 523i air filter