RC8B3.1 Aluminum Shock Standoffs for Avid's Carbon Shock Towers are 1mm shorter to keep the shock geometry the same because the pocket is removed from our CF towers so they don't split. Just like our standard length RC8B3.1 Aluminum Shock Standoffs, they are made from 7075-T6 (Hard Anodized for durability), 50% the weight of the stock steel standoffs, and a direct stock replacement.