Upgrade your mountain biking performance with the FOX SLS Coil Rear Shock Spring - engineered for durability, lightweight efficiency, and optimal shock responsiveness. Crafted from proprietary FOX Super Light Steel (SLS), this 500 lb. x 3.15" (80mm stroke) coil spring offers unmatched performance with innovative materials and engineering technology, making it the perfect choice for serious riders seeking precision, weight savings, and enhanced control. Materials & Advanced Engineering Constructed from high-grade lightweight steel, the FOX SLS coil spring features a proprietary surface treatment and stress relief process. This cutting-edge manufacturing technique allows the use of a smaller wire diameter and fewer coils, significantly reducing overall spring weight without sacrificing strength or durability. The result is a lighter, more efficient spring that enhances bike handling and reduces rider fatigue during demanding climbs and technical descents. Optimized Components & Compatibility Designed with an internal diameter of 35mm (1.385 inches), the FOX SLS spring seamlessly fits FOX coil shocks as well as models from Marzocchi, DVO, MRP, X-Fusion, and more. For precise fitment and compatibility, consult the fitment guide available at [Ride Fox Tech](https://tech.ridefox.com/bike/general-info/918/all-sls-and-standard-steel-rear-shock-spring-information). Performance & Ride Quality The lower unsprung weight of the FOX SLS spring significantly improves shock response and overall suspension performance. Ideal for aggressive trail riding, enduro, and downhill disciplines, this coil spring enhances shock sensitivity and damping control, providing riders with improved traction, stability, and confidence on rough terrain. Style & Aesthetic Appeal Featuring a vibrant orange finish, the FOX SLS coil spring not only delivers top-tier performance but also adds a bold pop of color to your bike's setup. Its sleek design embodies modern engineering and style, making it