Cummins 6B/5.9 3943875 Rear Exhaust Manifold PAI 181036CROSS REFERENCE: 3943875 3943874 3942259 APPLICATION: Cummins 6B 5. 9 BRAND: PAI 181036 Cummins 3943875 Rear Exhaust Manifold PAI 181036 intended for replacement truck and aftermarket truck. Provides reliable exhaust flow and reduces stress. All components are proudly manufactured in the U. S. A. by PAI Industries Inc., an ISO9001 certified company with over 50 years of experience in the heavy duty truck parts industry. This part is built brand new