Designed for up to 10,000 RPM. This heavy duty design features an oversized body and fulcrum with a triangulated profile for additional rigidity and strength. Accommodates most oversized valve springs. American-made roller bearings are in self-contained bearing-cups for extra low friction wear. Each set includes 16 extruded aluminum roller rockers and 16 poly locks. Product Features:1.5 Ratio 7/16 StudHeavy-Duty Extruded Aluminum Type with Needle Bearing TrunionsFits Small Block ChevyBlue Anodized FinishPoly Locks Included