Hot Racing 21.5mm adjustable compression spring damper set for Axial SCX30 and other custom Rock Crawler projects FEATURES: - CNC machined T6 aluminum shock bodies. - Precision machined stainless steel shock shaft for durability - Greace and o-ring damping - Three spring rates included - Hard anodized for durability, corrosion resistance, and great looks YOU WILL RECEIVE: - Four (4) assembled shocks - Four (4) silver springs (Soft) (11T) - Four (4) black springs (Med) (10T) - Four (4) gold springs (Firm) (9T) REQUIREMENTS: - Installation on vehicle - Recommended to use SPL10G08 increase smoothness SPECIFICATIONS: - Extended center to center length: 21.5mm (0.85 inch) - Compressed center to center length: 18mm (0.70 inch) - Overall length: mm (inch) - Body diameter: mm (inch) - Shaft diameter: mm (inch)