The Traxxion Dynamics Vented Shock Sock is a protective wrap for your rear shock absorber. It protects your investment from damage to the threads on the shock body, and the extremely vulnerable shock shaft. It is constructed of a breathable nylon material, and installs in seconds with a simple Velcro closure. Available in four sizes to fit all types of shock and spring combinations. Please measure your bike’s spring, and select the length needed. Measurement is in inches.