The SpinCo AR-15 carbine buffer spring is engineered for exceptional durability and performance, crafted from premium chrome silicon wire stock renowned for its resilience in high-stress environments, such as Formula One and motor valve springs. These springs endure up to 15,000,000 compression cycles in a single race, making them an ideal choice for your AR-15 carbine, which will experience significantly fewer cycles over its lifetime. To ensure lasting strength and reliability, each spring undergoes meticulous heat treatment, shot peening and is enhanced with Sprinco's proprietary formula, maintaining optimal spring efficiency throughout the lifespan of your rifle. The SpinCo Reduced power carbine buffer spring is an excellent upgrade for enhancing the long-term reliability and performance of your AR-15, providing peace of mind and superior functionality with every shot. For carbine length buffer tubes Color-coded as yellow Power reduction Constructed from chrome silicon wire material Heat-treated and shot peened