The SpinCo AR-10 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 carbine, which will experience significantly fewer cycles throughout its lifespan. To ensure lasting strength and efficiency, each spring undergoes meticulous heat treatment, shot peening and is enhanced with Sprinco's proprietary formula. This process guarantees that the spring maintains its optimal performance for as long as you own your rifle. The SpinCo Intermediate power carbine buffer spring is an excellent upgrade to enhance the long-term reliability and functionality of your AR-308, providing you with confidence and consistency in every shot. For .308 Cal carbine length buffer tubes Color-coded orange Enhanced power Constructed from chrome silicon wire material Heat-treated and shot peened