radius, 5/16" ball end. The radii on each end provide additional clearance for the Rocker adjuster at high lift and allow the pushrods to be installed either "up" or "down". The pushrods have a consistent .165" wall thickness, even in the tapered ends, which is thicker, stiffer and stronger than common .080" or .125" wall designs. These pushrods are made in the USA from heat-treated, one-piece chromemoly tubing, which is much stronger than typical 1000 Series Steels and will better handle extreme valve train setups.Full Set of (16) 8.650" Pushrods7/16" diameter offers additional stiffness and higher natural frequency 210˚