K&N universal air filter only for single turbo application, 4″, will flow upto around 900bhp.
 
Lots of other shapes and sizes available if required.  All filters are constructed with ultra-strong molded pliable rubber flanges which absorb vibration and allow for secure attachment and
can also be stretched for up to 1/16″ (1.5mm) to fit in-between
sizes. K&N universal air filters are washable and reusable.