Its unique process changes the Silicium/Chromium/Steel Alloy mix to produce a super hard, yet lightweight metal that will withstand the highest demands inflicted through MTB. To prevent shock rub, the spring is bi-convex in shape. This will allow the spring to progress freely without any friction when under load. Up to 40 per cent lighter than a steel spring, this hardened Super-light steel (SLS) spring has been designed to fit most rear shocks on the market by using Nukeproof’s unique Reducers and Spacers. This spring will work with metric shocks with an eye to eye between 210mm and 230mm, and with a stroke length between 47.5mm and 65mm. The spring will also work with standard shocks with an eye to eye between 200mm and 216mm, and a stroke length between 2” – 2.5” A pair of 38mm to 36mm reducers are included to allow this spring to be fitted to most shocks on the market. Spring Rate / Nukeproof Super Light (SLS) Weight We supply the correct spacers in the box to suit the rate of spring which you purchase.