Cane Creek Valt Steel Shock Spring. Features: Lightweight steel spring that offers a significant weight reduction over standard steel springs Larger inner diameter of the spring means it will fit Cane Creek shocks and most other options on the market Cane Creek and other shock brands may require conversion clip 1.43" internal dimension Specs: Stroke:2.5" Rate:400# Remarks:This model is designed for the 2013+ Specialized Enduro 29"