ENERGY HAS MADE DESIGN IMPROVEMENTS AND UPGRADES TO THE LOG SPLITTER VALVE AND THE DETENT KIT WILL FIT ALL ENERGY LOG SPLITTER VALVES. THE PARTS OF THE KIT WILL NOT INTERCHANGE, HOWEVER THE COMPLETE KIT WILL FIT ANY YEAR MODEL ENERGY VALVE. THE DETENT IS WHAT HOLD THE HANDLE BACK WHEN RETRACTING THE ROD AND KICKS IT OFF WHEN IT IS FULLY RETRACTED.