This is a Pro-Line Spring Assortment for the Slash Rear PowerStroke Shocks. FEATURES: Steel construction Silver and black in color Color coded stripes to identify firmness rating Makes it possible to adjust height and dual-rate rates YOU WILL RECEIVE: Six Primary (short) Springs Two Yellow Meduim Springs Two Blue Super Soft Springs Two Red Firm Six Secondary (long) Springs Two Blue Super Soft Springs Two Green Soft Springs Two Red Firm Springs REQUIREMENTS: Installation on shocks SPECIFICATIONS: Short Springs Long Springs Outer diameter: 20mm (0.79") Outer diameter: 20mm (0.79") Inner diameter: 16mm (0.63") Inner diameter: 16mm (0.63") Thickness: 1mm (0.04") Thickness: 1mm (0.04") length: 18.5mm (0.73") length: 55mm (2.17") lmm 6.23.10 ir/jxs &