Exhaust Manifold Header for 1990-1995 Nissan D21/Pickup 2.4l Engine Tubular Manifold Tri-y

O2 Sensor locations: 2 Header features 4-1 piping design design. 1.50" Primary Tubes 2.50" Outlet Head Flange Thickness: 716" Outlet Flange Thickness: 38" CNC machine flanges with TIG and MIG welded construction . Made from Stainless Steel. HPTorque Gains of 5-10. Professional installation is highly recommended Installation Instruction is NOT Included   Fitment: Nissan Hardbody 4WD 1990, 1991, 1992, 1993, 1994, 1995 4WD ONLY For Exact Years and Models, Please Check Compatibilities   Package including: 1 X Set of Header Exhaust System Hardwares such as Gaskets and Bolts as Shown in the Picture Above