The redesigned Bulletproof EGR cooler features a much more robust interior, with six round stainless-steel tubes in place of the factory three oval-shaped tubes. The benefits of this upgrade are staggering. Thanks to improved coolant flow, the EGR cooler can remove heat from exhaust gases effectively. Improved coolant flow cools exhaust gases better, which helps to prevent gunk deposits inside the cooler. The design also prevents the coolant from flash-boiling, thanks to decreased dwell time inside the unit. When coolant and exhaust gases pass through the EGR cooler as intended, heat can be removed from the exhaust gas before it is blended with the air charge. The result is cleaner combustion with fewer emissions.