Waxed CN-9100 XTR/Dura-Ace 12 Spd.Chains are waxed on demand using Silca Secret Blend Hot Wax. Wax offer greater component longevity, cleanliness, and better efficiency. The wax is a solid lubricant meaning that dirt and contaminants can't get in the chain which keeps your chain from wearing as quickly. In almost every application, we recommend wax. The Shimano CN M9100 features an extended inner link plate that connects seamlessly with chainring teeth for highly efficient drivetrain