FEATURES: Includes forward set sear, trigger, striker block kit, and spring kit Striker block kit includes striker block, spring, and talon tactical tool Spring kit includes 4 and 5.5lb trigger return springs, trigger return spring install tool, sear spring, and ram spring Results in trigger pull weight near 4lbs for competition or 5.5 for duty/carry Smooth uptake and reset Total trigger travel of .120" Improved safety features make the FSS a reliably safe trigger system Works with all Smith & Wesson M&P pistols in all centerfire calibers and configurations except M&P Shield Requires the use of the sear housing Mfg: Apex Tactical Specialties Inc SPECS: **REQUIRES the use of the larger 1/8 inch sear spring & plunger set up (included)**