Super Alloy Racing Springs are availible in 25lb increments and dyno tested. All springs are shipped with a dyno graph for proof of accuracy. Super Alloy Racing springs help to maximise suspension performance as well as reducing weight and increasing traction and sensitivity.Manufactured by Eibach to our SpecificationsDH spring stroke length: Designed for shocks with over 65mm of strokeMaterial: Silicone Chrome Vanadium steelPOM Bearings are required to fit your shock and are sold separately.The Super Alloy Racing POM Bearing system allows your SAR spring to fit any shock on the market. In addition to universal compatibility, these adapters reduce spring bind-up and reduce weight by enabling the use of the shortest possible spring.POM (polyoxymethylene) is a CNC grade polymer, allowing machining to precision tolerances whilst also preventing spring binding during use.*** Super Alloy Racing Springs NEED the POM Spacer Kit to convert to your shock, make sure to get the POM Spacer Kit that matches your shock.Spring markings: 250 lbs x 75mmItem SpecificationsI.D. (mm)36.5MaterialSteelSpring Weight250Stroke (ins)2.95 Super Alloy Racing SAR DH Rear Shock Spring UPC: 5060719340106