Replace your old, worn-out gearshift cable with the silky-smooth actuation of the Shimano Optislick Derailleur Cable. This shift cable features stainless steel with an Optislick coating that reduces friction and increases longevity with its corrosion-resistance. It's 1. 2mm in diameter and 2100mm in length, attaching to either the front or rear derailleur of your Shimano or SRAM drivetrain. Pair it with Shimano's SP41 cable housing for dependable shifts in nasty conditions experienced while you're mountain biking. It also works great for commuter rigs and road bikes.