Rear Air to Coil Spring Struts w/ Electric Fit for Mercedes-Benz S-Class W221 2007-2013 98884436Features: 1. Lowered height adjustment from 1" 3" which allow lower center of gravity and also add a more aggressive stance. 2. Adjustable pre load spring tension to reduce the shaking motion to a certain extent. 3. High Viscosity Index damper oil make damping more stable and smooth in wide temperature range. 4. 24 Clicks of Rebound Adjustments This allows you the ability to perfectly dial in your coilovers system. For a nice comfortable driving, set