The Apex Duty/Carry Spring Kit is a drop-in spring kit for S&W J-frame revolvers. It includes rebound and main springs plus an Apex XP firing pin, reducing the double-action pull by approximately 3 pounds while maintaining reliable ignition. It is tuned for duty and carry use rather than competition. Features: Drop-in spring kit Includes rebound spring, main spring, and Apex XP firing pin Reduces double-action pull by approximately 3 pounds Tuned for reliable ignition and duty/carry use Fits S&W J-frame centerfire revolvers, including models 31, 32, 34, 36, and 37.