ProFlow's Pro LS upgraded rocker arms feature high-quality rocker bodies that utilize the factory style pedestal mount. They are made of high-grade 4340 Alloy steel construction to ensure long-lasting durability and performance. This design replaces the factory bearing and powdered metal trunnion and utilizes a captive bearing design and a bearing steel trunnion. These rocker arms are a perfect upgrade for higher rate springs and performance camshafts. Proflow's Pro LS upgraded rocker arms come preassembled with heavy-duty trunnion kits, which saves you time and the additional cost of an installation tool.