Introducing the Apex Tactical Specialties 100051, an ideal kit for owners of the M&P Shield (9/40 only) who value performance and safety. It\'s a harmonious combination of the Apex Duty/Carry Kit and the Apex Action Enhancement Trigger. This Trigger Kit is designed to directly replace the factory hinged trigger with a solid aluminum body, offering a reduction of about 20% in pre-travel and over-travel.The trigger has a smooth face and features a center-mounted pivoting safety that retains the factory safety values. The Apex Duty/Carry Kit is expertly crafted to provide a smooth, consistent trigger pull which is approximately 2 lbs lighter, depending on factory tolerances. The benefits of this kit include shorter over-travel and a more noticeable trigger reset.Please note that the installation of the Ultimate Striker Block (USB) into the Shield slide should preferably be conducted by an armorer or gunsmith.