Catalytic Converter for Audi Q7 4.2 *Left&Right Design *Front Position *Direct ... CxH2x+2 + [(3x+1)/2]O2 → xCO2 + (x+1)H2O Direct Fit Catalytic Converter for Audi Q7 4.2 Vehicle Model ... : Audi Q7 4.2Vehicle Year:2007 ~ presentEngine:V ... PipeOperating Way : Three-Way Emission Standard:Euro 2, 3, 4 / EPA Tier 1, 2, 3 / CARB, Or Coating Standard ...