The Apex S&W J-Frame Duty/Carry Spring Kit is the next evolution of drop in parts. Installation of this kit reduces the trigger pull weight of your center fire J-Frame Smith & Wesson Revolver by approximately 3.0 lbs. from factory specifications. This high quality Apex J-frame S&W Spring Kit contains a new rebound slide spring, main spring, and an Apex XP firing pin kit. Installation requires no fitting or modification to the factory springs or parts on the Apex Duty/Carry kit. The model 103-106 spring kit Works with all modern centerfire J-frame revolvers with the frame mounted firing pin.