1997-2019 LS PERFORMANCE PARTS. The listed parts are the necessary parts for a Chevy/GM LS rocker arm trunnion upgrade. These listed parts combined with the proper camshaft and a rocker arm spring kit adds 125+ street horsepower to your LS engine without having to rebuild and/or take your engine out. This trunnion upgrade converts stock LS series rocker arms into captured roller trunnions for high-rpm street/race applications. These parts are brand new and were never installed. Stock rocker arms can be used with these parts in which is included also. PLEASE LOOK AT PICS AND SPECS! PRICE IS FIRM! $250.