This is a Apex Tactical Specialties Trigger known as the Apex M&P kit, model 100-079.
The Apex Action Enhancement Aluminum Trigger & Duty/Carry Kit for M&P (9/40 only) replaces the factory trigger" sear and safety plunger to deliver a smooth" crisp trigger pull that's ideal for duty/carry purposes.
Features:
Keeps pistol at a safe 5-5.5 lb. trigger pull weight
Reduces trigger pre-travel and over-travel by approx. 20%
Smooths trigger pull
Reduces reset
