Pipercross BMW G8X Car Panel Filter For M3 G80 & M4 G82Get the Pipercross Car Panel Filter For your BMW G8X M3 G80 or M4 G82. The low maintenance and long lifespan aspects of a Pipercross filter come from the special triple layer foam that is used on all Pipercross filters. The outer core is coarse foam designed to trap larger particles, the middle core is Medium foam designed to trap most particles and the inner core is fine foam which will trap the remainder of the particles. The triple layer foam