Reduced-power springs provide a 3.5 pound trigger pull when used with J.P. triggers, and a pull of 4.5 to 5 pounds when used with standard trigger components. Includes hammer spring, trigger return spring, and disconnector spring. Installation instructions also explain engagement surface polishing to obtain a smooth, reliable trigger. Gives A Smooth, Light Trigger Pull These are JP brand springs that will work with standard lower parts kit or aftermarket triggers for an AR-15.