K&N Air Filter For Audi B9 RS4 & S4 E-0646

K&N Replacement Air Filter For Audi RS4, S4, RS5 & S5 (B9)

Sale price£89.99GBP

Tax included. Shipping calculated at checkout

SKU: E-0646

Enhance the performance of your Audi B9 RS4, RS5, S5 & S4 with the K&N Replacement Air Filter. Designed for optimal airflow and filtration, this high-quality filter boosts engine efficiency and power. Enjoy improved throttle response and acceleration while maintaining superior engine protection. Easy to install and built to last, the K&N Replacement Air Filter is a must-have upgrade for Audi enthusiasts seeking peak performance from their vehicle.


  • Designed to increase horsepower & torque for the BMW B58 engine
  • Washable & Reusable
  • This K&N air filter lasts the lifetime of your vehicle.
  • Designed to boost horsepower and rate of acceleration
  • Can be cleaned and used again
  • High airflow with exceptional filtration
  • Lasts up to 50,000 miles before cleaning is required depending on driving conditions
  • Works with original equipment manufacturer vehicle electronics
  • Emissions legal in all 50 US states
  • Will NOT void vehicle warranty
  • Million Mile Limited Warranty®


  • Audi B9 RS4
  • Audi B9 S4
  • Audi B9 RS5
  • Audi B9 S5


K&N Million mile warranty