The SRAM X0 Low Clamp Front Derailleur uses X-glide front shifting technology, resulting in almost perfect shifting timing, & instantaneous shifts up or down even under load. This determination to provide the best most instantaneous shifting performance is complimented by a hard wearing high quality construction, that means your shifting performance will be safeguarded for years to come. The Exact Actuation system uses a 1:1 actuation ratio (shifter cable travel: derailleur movement) for 10 speed shifting. This Exact Actuation helps to simplify & stabilize the uneasy act of balancing rear derailleur hanger design, tight cog spacing & exact cable tension. The result: the easiest index shifting system to set up, & it stays that way.