The Apex Tactical Specialties S&W Shield Duty/Carry Action Enhancement Trigger Kit in Black is a combination of the Apex Shield Duty/Carry Action Enhancement Kit and the Apex Shield Action Enhancement Trigger. The Trigger Kit directly replaces the factory hinged trigger with a solid aluminum trigger body which reduces pre-travel and over-travel by approximately 20%. It features a smooth face with a center mounted pivoting safety that maintains factory safety values. This great Apex Tactical Specialties kit was designed to provide the M&P Shield pistol owner a smooth, consistent trigger pull that is approximately 2 lbs lighter (based on variations in factory tolerances) with the advantages of shorter over-travel and more detectable trigger reset. The kit itself is engineered to be drop-in and should not require further gunsmithing. However, armorer or gunsmith installation of the Ultimate Striker Block (USB) into the Shield slide is strongly recommended**.