Cummins 6C/ISC/ISL/QSC 3967751 Exhaust Manifold PAI 181039CROSS REFERENCE: 3967751 APPLICATION: Cummins 6C ISC ISL QSC BRAND: PAI 181039 Cummins 3967751 Exhaust Manifold PAI 181039 intended for commercial truck parts and diesel performance parts. Ensures controlled exhaust flow. Prevents leaks. Maintains consistent efficiency. 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.