Fit 88-99 Chevy/GMC trucks and SUV (2WD & 4WD) 5.0L/5.7L305/350 cu. Full length design for power gain from mid to high RPM range. Head flanges laser-cut from 5/16-inch thick steel plates. Flanges flattened by hydraulic press for precise and leak-free seal. All joints TIG welded for resistance against cracking and wearing. Black paint coating that withstands up to 500 degrees Celsius. Long transition collector for decreased back pressure. Fully mandrel bent tubes made of 16-gauge mild steel.