Upgrade your M&P 4 inches, 4.25 inches and 5 inches models with our premium replacement flat Wire spring, specifically engineered for the Ed Brown Fueled M&P series. This advanced recoil spring is designed to deliver unparalleled durability and performance, featuring a 15lb tension as standard. Experience the longest-lasting handgun recoil spring on the market, boasting a service life up to ten times greater than traditional coil springs. With a recommended replacement interval of 30,000 to 40,000 rounds, this flat wire spring ensures consistent reliability and optimal performance, making it an essential component for serious shooters seeking longevity and precision in their firearms.