Product Description Specifications With a 2024 aluminum rocker and 8620 hardened steel shaft, this shaft-mount rocker system adds stability to the engine which frees up horsepower. This system features 1.8 ratio rockers for GM LS1, LS2 and LS6. Category: Engine Components>Rocker Arms Core: N LTL: N MPN: 1501CPG Proposition 65: Y Special Order: Y