Expect to see gains of 5-10bhp compared to the original Airbox.

Enhanced induction sound, great looks and loud recirculation dumpvalve noise on let off. And only £149.95

• Features.
• Removes ugly original plastic & restrictive airbox
• Adds power and torque, 
• more responsive and exciting driving experience
• Enhanced induction sound and turbo recirculation noise (dumpvalve 'psssh')
• free flowing Airfilter & optional k&n dry charger filter cover
• CNC maf sensor boss with AS engraved logo
• Powder coated alloy heat-shield with 80mm cold feed pipe which directs air to bottom of filter
• Cold feed pipe, secure to bottom of heat-shield and secures to lower boost hose, or attach to front lower bumper as shown in the photo
• Adds style to your ST engine bay
• Easy fitting, takes less than 15-20 minutes to install

Conclusion. It's easy to fit, looks great, sounds even better, doesn't cost the earth and can be put back to standard within 10 minutes (warranty)