Mack 736GB421M2 Fuel Injector PAI 891946CROSS REFERENCE: 736GB421M2 736GB421M2X 25101645 APPLICATION: Mack Aset Multiple Use Application. BRAND: PAI 891946 Mack 736GB421M2 Fuel Injector PAI 891946. Replacement parts and aftermarket parts. Provides controlled atomization and supports reliable combustion 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