Black Internal Spring Shock Absorbers. Instead of using springs on the outside these feature an internal spring pushing down on the piston giving the dampening effect. These shock absorbers are sold individually. Features:CNC machined aluminum shock body.Easy load shock seal assembly.Originally designed for 1/10 RC Cars, works great for Skeeride 2.80 and 90mm shocks come with soft/medium/hard springs to choose from.63 and 73mm shocks come with only 1 set of springs.Shocks are oil adjustable but do not come oil filled. Specifications:Material: Aluminum and plasticBall fixing hole aperture: 3mmShock body diameter: 10mmHole to hole length: 63, 73, 80, 90mmEnd to end length: 72, 82, 90, 100mm Click here for shock specifications for different model builds. Please note in some instances shocks may require standoffs, shims, modified design files, spring modification, oil adjustment or ball grinding to fit perfectly. Please do your research and ask if you have questions.