Originally designed as a semi-drop in replacement for Performance Center revolvers, the Apex Evolution IV K/L-Frame Hammer is redesigned using the same pinned sear and stirrup found on the Performance Center hammer. Additionally, the Apex Evolution IV Hammer replaces MIM components found in Smith & Wesson non-Performance Center revolvers and Performance Center revolvers made after January 2012. Manufactured from heat treated 17-4 Ph stainless steel, the hammer is wire EDM and CNC machined then surface ground to ensure consistent performance. Features: Converts revolver to double action only (DAO) Lacks a hammer spur for cocking to single action